According to Office Party of mass line education practice activities led group of unified arrangements, units main led to for cadres workers Shang a times party lecture, due to himself level limited, only put this stage concentrated learning of experience today and everyone common with learning exchange, purpose is let we further deep understanding mass line of connotation, insisted party of mass line, do masses work, following main from four a aspects told: a, and full awareness party of mass line education practice activities of major meaning Party's 18 major distinct proposed to focus on the party's advanced nature and purity, in the party, with \c and clean for the people\content of the party's mass line and educational practice. This is comrade XI Jinping as party General Secretary and adhere to strictly administering the party, strengthen the party's major decision is in line with the public expectations and strengthening the construction of learning-oriented service innovation of Marxist party's major deployment, is the important measure to advance the great cause of socialism with Chinese characteristics. First, carry out the party's mass line in education practice, was carrying 18 of the party spirit, summon a powerful force for realizing the great rejuvenation of the Chinese nation the Chinese dream of urgent needs. Party's 18 to promote strategic deployment to building socialism with Chinese characteristics, presents two 100-year goal, namely, by 2020 China's gross domestic product and per capita income of urban and rural residents in 2010 on the basis of double complete the building of a well-off society; the middle of this century into a prosperous, democratic, civilized and harmonious Socialist modern country, and on this basis, the Chinese dream of realizing the great rejuvenation of the Chinese nation. 18 Congress of the party, Comrade XI Jinping repeatedly expounded the Chinese dream. The basic connotation of the Chinese dream, is the national prosperity, national revitalization, the happiness of the people, China important to follow is to keep China Road, carry forward the spirit and cohesion strength of China, dream dreams of the people of China, but determined confidence, enhance self-awareness, achieve self-reliance, to build a stronger China, civilization, harmony, beauty, China, China, China. Strategic conception of China was 18 the spirit of the enrichment and development of the party, conscientiously study the Chinese dream, leading people to hard to realize the Chinese dream, mass education activities in depth the fundamental starting point and ending point. Strengthen the education of the party's mass line, helps to train the collective consciousness of the unity of the party and the people, playing the Chinese dream ideological bases. Comrade Mao Zedong stressed that parties should have \common language\st countries must have \of will\has 6
【学生练习】 在上图中的B图和C图上绘出晨昏线。 【学生回答】略
【讲解】各种不同光照图中晨昏线的画法
1、 侧面图： 夏至日（6.22） 冬至日（12.22） N N
2、北极上空图： N N
3、南极上空图
S S
【学生活动】用地球仪演示晨昏线如何画侧面图和极地上空图
【过渡】假如同学们就是太阳，地球对着太阳的一半是白天，背着太阳的一半是黑天，由于每天地球围绕太阳自西向东转，东边的地点比西边先看到日出，东边的时刻要比西边的时刻早。当北京正对着太阳的时候，也就是说北京是12点时，纽约还是黑夜。古时候各地都把正
roved that a people and a nation, if it does not have its own spiritual pillar, there is no unity of spiritual support, it means that no soul, will lose cohesion and vitality. Figuratively speaking, a sack of potatoes, quantity cannot be too a team, form a joint force; only like granite, so closely United to form invincible, no difficult means of strength. National rejuvenation of Chinese dream, not only embodies the common interests and pursuits, and covers a variety of groups and classes, has a wide applicability and inclusive, with a strong integrating force and lead the force. She embodies the aspirations of several generations of Chinese, reflecting today ... Into sex and purity, and the inevitable requirement of constantly improving the party's governing capacity. Strengthening the construction of the advanced nature and purity, the core problem is always maintaining the party's flesh-and-blood ties with the masses, so that our party will always be the most wholehearted support of the masses. Must take the
fundamental interests of the overwhelming majority of the people as the party all the starting point and ending point, the party has always been a common fate with the masses, this is the magic weapon for our party to always maintain the advanced nature and purity. Strengthening the construction of party's advanced nature and purity and enhancing the party's ruling ability will eventually be implemented to realize, safeguard and develop the fundamental interests of the overwhelming majority of the people. All the work merits this is a measure of the party's fundamental standards, is a measure of the party's advanced nature and purity standards. Believe who, depending on who, who, standing on the position of the overwhelming majority of the people are always, always realize, safeguard and develop the fundamental interests of the overwhelming majority of the people, it is a touchstone of the Marxist party of judgement, is also sign of Marxist party is different from other political parties. Marxist political party has a clear political position and historical mission: for the interests of the vast majority of people, committed to the fundamental interests of the overwhelming majority of the people. From the day of the establishment of the Chinese Communist Party, always adhere to basic principles of historical materialism, for the interests of the most people as their goal, always serving as its fundamental purpose and values. Fully trust the masses, closely rely on the masses maintain flesh-and-blood ties with the masses is always the source of our party full of vigor and vitality, is always the most determined in the development of our party and our country. Conscientiously accept supervision by the masses, pay attention to listen to the masses ' assessment, which itself was the party's advanced nature and purity into practical action to realize the fundamental interests of the overwhelming majority of the people. At present, the party committees and leading cadres and the Government generally value the close relations with the masses, do a lot of productive work, but there are still some6
According to Office Party of mass line education practice activities led group of unified arrangements, units main led to for cadres workers Shang a times party lecture, due to himself level limited, only put this stage concentrated learning of experience today and everyone common with learning exchange, purpose is let we further deep understanding mass line of connotation, insisted party of mass line, do masses work, following main from four a aspects told: a, and full awareness party of mass line education practice activities of major meaning Party's 18 major distinct proposed to focus on the party's advanced nature and purity, in the party, with \c and clean for the people\content of the party's mass line and educational practice. This is comrade XI Jinping as party General Secretary and adhere to strictly administering the party, strengthen the party's major decision is in line with the public expectations and strengthening the construction of learning-oriented service innovation ofMarxist party's major deployment, is the important measure to advance the great cause of socialism with Chinese characteristics. First, carry out the party's mass line in education practice, was carrying 18 of the party spirit, summon a powerful force for realizing the great rejuvenation of the Chinese nation the Chinese dream of urgent needs. Party's 18 to promote strategic deployment to building socialism with Chinese characteristics, presents two 100-year goal, namely, by 2020 China's gross domestic product and per capita income of urban and rural residents in 2010 on the basis of double complete the building of a well-off society; the middle of this century into a prosperous, democratic, civilized and harmonious Socialist modern country, and on this basis, the Chinese dream of realizing the great rejuvenation of the Chinese nation. 18 Congress of the party, Comrade XI Jinping repeatedly expounded the Chinese dream. The basic connotation of the Chinese dream, is the national prosperity, nationalrevitalization, the happiness of the people, China important to follow is to keep China Road, carry forward the spirit and cohesion strength of China, dream dreams of the people of China, but determined confidence, enhance self-awareness, achieve self-reliance, to build a stronger China, civilization, harmony, beauty, China, China, China. Strategic conception of China was 18 the spirit of the enrichment and development of the party, conscientiously study the Chinese dream, leading people to hard to realize the Chinese dream, mass education activities in depth the fundamental starting point and ending point. Strengthen the education of the party's mass line, helps to train the collective consciousness of the unity of the party and the people, playing the Chinese dream ideological bases. Comrade Mao Zedong stressed that parties should have \nguage\st countries must have \of will\has午太阳位置最高的时刻定为12点，因而各地的12点是不同的，所以其他时刻各地也不相同，这种因地而异的时刻，称为地方时。这就是我们要学习的下一个问题： 【板书】二、时区和日界线 (出示标明北京、纽约的地球仪) 【教师边演示边讲解】 【板书】1.地方时
【讨论】请学生看教材P16～17页思考：我们看雅典奥运会直播现场，为什么大多数会在我们的晚上或夜间进行？ 【学生回答】略
【转折】为了克服时间上的混乱，1884年在华盛顿召开了一次国际经度会议，在会上创立了标准时制度，明确了世界上的时区划分、时间计算等问题。 【板书】2.时区的划分和区时的确定 (出示时区和国际日界线图)
【提问】1.地球自转一周需要多少小时?
2.地球每小时转多少个经度?
【教师指图讲解】由于地球每24小时自转一周，一小时转15个经度。因此，国际上规定，每隔15°划为一个时区，全球可分为24个时区。以本初子午线为基准，从西经7.5°至东经7.5°，划为中时区，或叫零时区。在中时区以东，依次划分为东一区至东十二区；在中时区以西，
roved that a people and a nation, if it does not have its own spiritual pillar, there is no unity of spiritual support, it means that no soul, will lose cohesion and vitality. Figuratively speaking, a sack of potatoes, quantity cannot be too a team, form a joint force; only like granite, so closely United to form invincible, no difficult means of strength. National rejuvenation of Chinese dream, not only embodies the common interests and pursuits, and covers a variety of groups and classes, has a wide applicability and inclusive, with a strong integrating force and lead the force. She embodies the aspirations of several generations of Chinese, reflecting today ... Into sex and purity, and the inevitable requirement of constantly improving the party's governing capacity. Strengthening the construction of the advanced nature and purity, the core problem is always maintaining the party's flesh-and-blood ties with the masses, so that our party will always be the most wholehearted support of the masses. Must take the
fundamental interests of the overwhelming majority of the people as the party all the starting point and ending point, the party has always been a common fate with the masses, this is the magic weapon for our party to always maintain the advanced nature and purity. Strengthening the construction of party's advanced nature and purity and enhancing the party's ruling ability will eventually be implemented to realize, safeguard and develop the fundamental interests of the overwhelming majority of the people. All the work merits this is a measure of the party's fundamental standards, is a measure of the party's advanced nature and purity standards. Believe who, depending on who, who, standing on the position of the overwhelming majority of the people are always, always realize, safeguard and develop the fundamental interests of the overwhelming majority of the people, it is a touchstone of the Marxist party of judgement, is also sign of Marxist party is different from other political parties. Marxist political party has a clear political position and historical mission: for the interests of the vast majority of people, committed to the fundamental interests of the overwhelming majority of the people. From the day of the establishment of the Chinese Communist Party, always adhere to basic principles of historical materialism, for the interests of the most people as their goal, always serving as its fundamental purpose and values. Fully trust the masses, closely rely on the masses maintain flesh-and-blood ties with the masses is always the source of our party full of vigor and vitality, is always the most determined in the development of our party and our country. Conscientiously accept supervision by the masses, pay attention to listen to the masses ' assessment, which itself was the party's advanced nature and purity into practical action to realize the fundamental interests of the overwhelming majority of the people. At present, the party committees and leading cadres and the Government generally value the close relations with the masses, do a lot of productive work, but there are still some- 7 -
According to Office Party of mass line education practice activities led group of unified arrangements, units main led to for cadres workers Shang a times party lecture, due to himself level limited, only put this stage concentrated learning of experience today and everyone common with learning exchange, purpose is let we further deep understanding mass line of connotation, insisted party of mass line, do masses work, following main from four a aspects told: a, and full awareness party of mass line education practice activities of major meaning Party's 18 major distinct proposed to focus on the party's advanced nature and purity, in the party, with \c and clean for the people\content of the party's mass line and educational practice. This is comrade XI Jinping as party General Secretary and adhere to strictly administering the party, strengthen the party's major decision is in line with the public expectations and strengthening the construction of learning-oriented service innovation of Marxist party's major deployment, is the important measure to advance the great cause of socialism with Chinese characteristics. First, carry out the party's mass line in education practice, was carrying 18 of the party spirit, summon a powerful force for realizing the great rejuvenation of the Chinese nation the Chinese dream of urgent needs. Party's 18 to promote strategic deployment to building socialism with Chinese characteristics, presents two 100-year goal, namely, by 2020 China's gross domestic product and per capita income of urban and rural residents in 2010 on the basis of double complete the building of a well-off society; the middle of this century into a prosperous, democratic, civilized and harmonious Socialist modern country, and on this basis, the Chinese dream of realizing the great rejuvenation of the Chinese nation. 18 Congress of the party, Comrade XI Jinping repeatedly expounded the Chinese dream. The basic connotation of the Chinese dream, is the national prosperity, national revitalization, the happiness of the people, China important to follow is to keep China Road, carry forward the spirit and cohesion strength of China, dream dreams of the people of China, but determined confidence, enhance self-awareness, achieve self-reliance, to build a stronger China, civilization, harmony, beauty, China, China, China. Strategic conception of China was 18 the spirit of the enrichment and development of the party, conscientiously study the Chinese dream, leading people to hard to realize the Chinese dream, mass education activities in depth the fundamental starting point and ending point. Strengthen the education of the party's mass line, helps to train the collective consciousness of the unity of the party and the people, playing the Chinese dream ideological bases. Comrade Mao Zedong stressed that parties should have \common language\st countries must have \of will\has 8 依次划分为西一区至西十二区。东十二区和西十二区各跨经度7.5°，合为一个时区，称为东西十二区。
(让同学看书时区和国际日界线图)
【提问】北京、东京、莫斯科、开罗、伦敦、纽约、华盛顿各在哪个时区? 【教师指图讲解】每个时区跨经度15°，同一时区各处地方时也不相同，因此国际上规定，每个时区的中央经线，叫做该时区的“标准经线”，标准经线上的时间，便是整个时区的“区时”。例如，中时区的中央经线是零度经线，零度经线的地方时便是中时区的区时；北京处在东八区，东经120°是东八区的中央经线，因此北京时间是采用东经120°的地方时，即东八区的区时。
【提问】东九区和西五区的标准经线各是多少度? 【学生回答】 135°E 75°W
【转折】请同学们做一做教材P17读图思考题5（备注：教师指出，要解决这个问题，需要我们学会计算时间）
(出示投影片：区时计算图解)
【教师指图讲解计算方法】相邻两个时区的区时相差l小时。在任意两个时区之间，相差几个时区，就相差几个小时，其中较东的时区，区时早。因此，出国旅行的人，向东每跨入一个时区，应把表往前拨一小时，向西每跨入一个时区，应把表倒拨一小时，这样才能使游客的表与当地时间一致。
(出示投影片：例题当莫斯科是5点时，伦敦、华盛顿各是几点?) 教师带学生解题： 【提问】
1.伦敦、莫斯科各在哪个时区?
2.伦敦和莫斯科相差几个时区?几个小时? 3.伦敦在莫斯科的东边，还是西边? 4.伦敦的时刻比莫斯科的早还是晚? 5.当莫斯科是五点时，伦敦是几点? (华盛顿同理)
【教师总结计算方法】1.求区时差，同区相减、异区相加；2.东边的时刻总比西边的时刻早。求东边的时刻加时差，求西边的时刻减时差。
(备注：出示投影片：练习题当北京是21点时，东京、开罗、纽约各是几点?)
【介绍】（教师根据学生的问题加以指导并讲解）实际上，在分区计时的基础上，世界各国根据本国的具体情况，采用了一些特别的计时方法。有的国家根据领土跨越经度广的实际，不同的时区分别采用不同的区时作为标准时间，如美国本土部分由东到西包括西5区、西6区、西7区、西8区四个时区。这四个时区分别采用不同的区时作为标准时间，这就是常说的东部时间、中部时间、山岳时间和太平洋时间。；有的国家为了国内各地联系方便，统一采用首都所在地的区时，如我国跨五个时区，为了便于各地区之间的联系与协调，全国统一采用北京所在的东八区的区时（即东经120度的地方时），这就是“北京时间”；还有的国家为了充分利用太阳照明，将本国东部时区的中央经线的地方时作为全国统一使用的时间标准。
roved that a people and a nation, if it does not have its own spiritual pillar, there is no unity of spiritual support, it means that no soul, will lose cohesion and vitality. Figuratively speaking, a sack of potatoes, quantity cannot be too a team, form a joint force; only like granite, so closely United to form invincible, no difficult means of strength. National rejuvenation of Chinese dream, not only embodies the common interests and pursuits, and covers a variety of groups and classes, has a wide applicability and inclusive, with a strong integrating force and lead the force. She embodies the aspirations of several generations of Chinese, reflecting today ... Into sex and purity, and the inevitable requirement of constantly improving the party's governing capacity. Strengthening the construction of the advanced nature and purity, the core problem is always maintaining the party's flesh-and-blood ties with the masses, so that our party will always be the most wholehearted support of the masses. Must take the
fundamental interests of the overwhelming majority of the people as the party all the starting point and ending point, the party has always been a common fate with the masses, this is the magic weapon for our party to always maintain the advanced nature and purity. Strengthening the construction of party's advanced nature and purity and enhancing the party's ruling ability will eventually be implemented to realize, safeguard and develop the fundamental interests of the overwhelming majority of the people. All the work merits this is a measure of the party's fundamental standards, is a measure of the party's advanced nature and purity standards. Believe who, depending on who, who, standing on the position of the overwhelming majority of the people are always, always realize, safeguard and develop the fundamental interests of the overwhelming majority of the people, it is a touchstone of the Marxist party of judgement, is also sign of Marxist party is different from other political parties. Marxist political party has a clear political position and historical mission: for the interests of the vast majority of people, committed to the fundamental interests of the overwhelming majority of the people. From the day of the establishment of the Chinese Communist Party, always adhere to basic principles of historical materialism, for the interests of the most people as their goal, always serving as its fundamental purpose and values. Fully trust the masses, closely rely on the masses maintain flesh-and-blood ties with the masses is always the source of our party full of vigor and vitality, is always the most determined in the development of our party and our country. Conscientiously accept supervision by the masses, pay attention to listen to the masses ' assessment, which itself was the party's advanced nature and purity into practical action to realize the fundamental interests of the overwhelming majority of the people. At present, the party committees and leading cadres and the Government generally value the close relations with the masses, do a lot of productive work, but there are still some8
According to Office Party of mass line education practice activities led group of unified arrangements, units main led to for cadres workers Shang a times party lecture, due to himself level limited, only put this stage concentrated learning of experience today and everyone common with learning exchange, purpose is let we further deep understanding mass line of connotation, insisted party of mass line, do masses work, following main from four a aspects told: a, and full awareness party of mass line education practice activities of major meaning Party's 18 major distinct proposed to focus on the party's advanced nature and purity, in the party, with \c and clean for the people\content of the party's mass line and educational practice. This is comrade XI Jinping as party General Secretary and adhere to strictly administering the party, strengthen the party's major decision is in line with the public expectations and strengthening the construction of learning-oriented service innovation ofMarxist party's major deployment, is the important measure to advance the great cause of socialism with Chinese characteristics. First, carry out the party's mass line in education practice, was carrying 18 of the party spirit, summon a powerful force for realizing the great rejuvenation of the Chinese nation the Chinese dream of urgent needs. Party's 18 to promote strategic deployment to building socialism with Chinese characteristics, presents two 100-year goal, namely, by 2020 China's gross domestic product and per capita income of urban and rural residents in 2010 on the basis of double complete the building of a well-off society; the middle of this century into a prosperous, democratic, civilized and harmonious Socialist modern country, and on this basis, the Chinese dream of realizing the great rejuvenation of the Chinese nation. 18 Congress of the party, Comrade XI Jinping repeatedly expounded the Chinese dream. The basic connotation of the Chinese dream, is the national prosperity, nationalrevitalization, the happiness of the people, China important to follow is to keep China Road, carry forward the spirit and cohesion strength of China, dream dreams of the people of China, but determined confidence, enhance self-awareness, achieve self-reliance, to build a stronger China, civilization, harmony, beauty, China, China, China. Strategic conception of China was 18 the spirit of the enrichment and development of the party, conscientiously study the Chinese dream, leading people to hard to realize the Chinese dream, mass education activities in depth the fundamental starting point and ending point. Strengthen the education of the party's mass line, helps to train the collective consciousness of the unity of the party and the people, playing the Chinese dream ideological bases. Comrade Mao Zedong stressed that parties should have \nguage\st countries must have \of will\has 为了避免日期的紊乱，1884年的国际经度会议，还规定了原则上以180°经线作为地球上“今天”和“昨天”的分界线，并把这条分界线叫做“国际日期变更线”，现改称“国际日界线”。地球上新的一天就从这里开始。 【课堂小结】
【提问】1.今天我们主要学习了哪些内容?
2.已知某区区时，如何计算另一时区的区时?
教师根据学生回答小结：地球自转→地方时→时差→时间混乱→时区的划分和区时计算。 【探究性作业】教材P18活动题。
板书设计
第二课时：地球自转与时差
一、晨昏线（圈） 1晨昏圈概念： 2晨昏线的画法： 二、时区和日界线 1. 地方时
2. 2.时区的划分和区时的确定
1.3.3 地球公转与季节
【教学目标】
roved that a people and a nation, if it does not have its own spiritual pillar, there is no unity of spiritual support, it means that no soul, will lose cohesion and vitality. Figuratively speaking, a sack of potatoes, quantity cannot be too a team, form a joint force; only like granite, so closely United to form invincible, no difficult means of strength. National rejuvenation of Chinese dream, not only embodies the common interests and pursuits, and covers a variety of groups and classes, has a wide applicability and inclusive, with a strong integrating force and lead the force. She embodies the aspirations of several generations of Chinese, reflecting today ... Into sex and purity, and the inevitable requirement of constantly improving the party's governing capacity. Strengthening the construction of the advanced nature and purity, the core problem is always maintaining the party's flesh-and-blood ties with the masses, so that our party will always be the most wholehearted support of the masses. Must take the
fundamental interests of the overwhelming majority of the people as the party all the starting point and ending point, the party has always been a common fate with the masses, this is the magic weapon for our party to always maintain the advanced nature and purity. Strengthening the construction of party's advanced nature and purity and enhancing the party's ruling ability will eventually be implemented to realize, safeguard and develop the fundamental interests of the overwhelming majority of the people. All the work merits this is a measure of the party's fundamental standards, is a measure of the party's advanced nature and purity standards. Believe who, depending on who, who, standing on the position of the overwhelming majority of the people are always, always realize, safeguard and develop the fundamental interests of the overwhelming majority of the people, it is a touchstone of the Marxist party of judgement, is also sign of Marxist party is different from other political parties. Marxist political party has a clear political position and historical mission: for the interests of the vast majority of people, committed to the fundamental interests of the overwhelming majority of the people. From the day of the establishment of the Chinese Communist Party, always adhere to basic principles of historical materialism, for the interests of the most people as their goal, always serving as its fundamental purpose and values. Fully trust the masses, closely rely on the masses maintain flesh-and-blood ties with the masses is always the source of our party full of vigor and vitality, is always the most determined in the development of our party and our country. Conscientiously accept supervision by the masses, pay attention to listen to the masses ' assessment, which itself was the party's advanced nature and purity into practical action to realize the fundamental interests of the overwhelming majority of the people. At present, the party committees and leading cadres and the Government generally value the close relations with the masses, do a lot of productive work, but there are still some- 9 -
According to Office Party of mass line education practice activities led group of unified arrangements, units main led to for cadres workers Shang a times party lecture, due to himself level limited, only put this stage concentrated learning of experience today and everyone common with learning exchange, purpose is let we further deep understanding mass line of connotation, insisted party of mass line, do masses work, following main from four a aspects told: a, and full awareness party of mass line education practice activities of major meaning Party's 18 major distinct proposed to focus on the party's advanced nature and purity, in the party, with \c and clean for the people\content of the party's mass line and educational practice. This is comrade XI Jinping as party General Secretary and adhere to strictly administering the party, strengthen the party's major decision is in line with the public expectations and strengthening the construction of learning-oriented service innovation of Marxist party's major deployment, is the important measure to advance the great cause of socialism with Chinese characteristics. First, carry out the party's mass line in education practice, was carrying 18 of the party spirit, summon a powerful force for realizing the great rejuvenation of the Chinese nation the Chinese dream of urgent needs. Party's 18 to promote strategic deployment to building socialism with Chinese characteristics, presents two 100-year goal, namely, by 2020 China's gross domestic product and per capita income of urban and rural residents in 2010 on the basis of double complete the building of a well-off society; the middle of this century into a prosperous, democratic, civilized and harmonious Socialist modern country, and on this basis, the Chinese dream of realizing the great rejuvenation of the Chinese nation. 18 Congress of the party, Comrade XI Jinping repeatedly expounded the Chinese dream. The basic connotation of the Chinese dream, is the national prosperity, national revitalization, the happiness of the people, China important to follow is to keep China Road, carry forward the spirit and cohesion strength of China, dream dreams of the people of China, but determined confidence, enhance self-awareness, achieve self-reliance, to build a stronger China, civilization, harmony, beauty, China, China, China. Strategic conception of China was 18 the spirit of the enrichment and development of the party, conscientiously study the Chinese dream, leading people to hard to realize the Chinese dream, mass education activities in depth the fundamental starting point and ending point. Strengthen the education of the party's mass line, helps to train the collective consciousness of the unity of the party and the people, playing the Chinese dream ideological bases. Comrade Mao Zedong stressed that parties should have \common language\st countries must have \of will\has 10 1．使学生理解黄赤交角的概念及由其产生的太阳直射点移动，并能正确画图表示。 2．．使学生理解地球公转的地理意义，并会画图表示并说明正午太阳高度及昼夜长短的变化。 3．使学生理解四季的形成和划分。 【教学重点】
1．黄赤交角和太阳直射点移动。 2．正午太阳高度及昼夜长短的变化。 3．阅读和画太阳照射地球的示意图。 【教学难点】
1．黄赤交角和太阳直射点移动 2．正午太阳高度及昼夜长短的变化 【教学媒体】
投影仪、投影片、小地球仪（描出回归线）每组学生四个，教师两个，黄道面及支架每组一个，灯泡和试管架各一个、黄赤交角模型。
【教学过程】
【导入新课】 上节课我们学习了地球运动的形式——自转和公转，对于二者对地球的影响是否孤立的呢？答案是否定的，自转和公转的叠加构成地球的运动，那么二者是如何相互作用共同影响地球的呢？这就是我们今天要讲的： 【板书】第三课时：地球公转与季节
【讲解】地球自转和公转的关系，可以用赤道平面和黄道平面的关系表示。 【演示】地球公转和二分二至时地球与太阳的相对位置。
【读图】《二分二至时地球的位置与黄赤交角》 【讲解】地球公转有两个重要特点：一是地轴与公转轨道面（黄道面）保持66°34ˊ的交角；二是地轴的空间指向基本不变，北极延长线指向北极星。因此，地球自转形成的赤道平面和公转形成的黄道平面构成23°26ˊ的交角，称为黄赤交角。它是地球自转和公转运动相互叠 【板书】一、黄赤交角：23°26ˊ
【讲解】 地球上的光热来自太阳，冷热的变化也
与接收到的太阳光热密切联系。地球比太阳小得多，因此我们一般把太阳照射到地球的光线看成是一组平行光。
【投影片】 平行光照射球体时直射点的图形特征
【提问】 地球表面有几个直射点，在示意图上如何表示？ 学生观察回答。
【小结】 球面上只有一个直射点。在图上表示的这条直射光线恰好可以把圆心和直射点相连。 【演示】 演示步骤：
（1）一个小地球仪在灯泡照射下，高光（最亮）点就是直射点；
roved that a people and a nation, if it does not have its own spiritual pillar, there is no unity of spiritual support, it means that no soul, will lose cohesion and vitality. Figuratively speaking, a sack of potatoes, quantity cannot be too a team, form a joint force; only like granite, so closely United to form invincible, no difficult means of strength. National rejuvenation of Chinese dream, not only embodies the common interests and pursuits, and covers a variety of groups and classes, has a wide applicability and inclusive, with a strong integrating force and lead the force. She embodies the aspirations of several generations of Chinese, reflecting today ... Into sex and purity, and the inevitable requirement of constantly improving the party's governing capacity. Strengthening the construction of the advanced nature and purity, the core problem is always maintaining the party's flesh-and-blood ties with the masses, so that our party will always be the most wholehearted support of the masses. Must take the
fundamental interests of the overwhelming majority of the people as the party all the starting point and ending point, the party has always been a common fate with the masses, this is the magic weapon for our party to always maintain the advanced nature and purity. Strengthening the construction of party's advanced nature and purity and enhancing the party's ruling ability will eventually be implemented to realize, safeguard and develop the fundamental interests of the overwhelming majority of the people. All the work merits this is a measure of the party's fundamental standards, is a measure of the party's advanced nature and purity standards. Believe who, depending on who, who, standing on the position of the overwhelming majority of the people are always, always realize, safeguard and develop the fundamental interests of the overwhelming majority of the people, it is a touchstone of the Marxist party of judgement, is also sign of Marxist party is different from other political parties. Marxist political party has a clear political position and historical mission: for the interests of the vast majority of people, committed to the fundamental interests of the overwhelming majority of the people. From the day of the establishment of the Chinese Communist Party, always adhere to basic principles of historical materialism, for the interests of the most people as their goal, always serving as its fundamental purpose and values. Fully trust the masses, closely rely on the masses maintain flesh-and-blood ties with the masses is always the source of our party full of vigor and vitality, is always the most determined in the development of our party and our country. Conscientiously accept supervision by the masses, pay attention to listen to the masses ' assessment, which itself was the party's advanced nature and purity into practical action to realize the fundamental interests of the overwhelming majority of the people. At present, the party committees and leading cadres and the Government generally value the close relations with the masses, do a lot of productive work, but there are still some10