The teacher designed the game to make the deskmate say antonyms. (Attract students' interest by saying antonyms)

Q: Who will tell the teacher antonyms? (Students' interest is stimulated)

These are the antonyms of Chinese that we have learned. So, do you know how these antonyms are compared in our math study? Today, the teacher will discuss with you the function of antonyms in the following mathematics, which leads to the topic of "comparison".

Second, the new curriculum exploration

1) overall perception situation map. (The courseware shows the situation map)

Teacher: Look carefully and tell me what's in the picture.

Students can distinguish what is in the picture through observation and cultivate the ability of careful observation. Give affirmation and encouragement to students' answers.

2) Proportion and thickness.

Question: By the way, who has more clothes? What can you do? (Counting everyone's clothes)

Teacher: Xiaoming said that mom has a lot of clothes? Do you agree with Xiao Ming? How did you know?

Multimedia highlights the enlarged wardrobe for students to observe. )

Students express their opinions and encourage them to speak their minds boldly.

Q: Then whose clothes are thicker? What can you do?

(Multimedia demonstration of thinning process) ...

Summary: Students compare their mothers' clothes in many good ways. Many problems can also be found by comparison.

3) Compare the length.

Teacher: It's autumn and it's very cold. My mother prepared three coats to hang in the closet. What did you find?

Students think independently first, then discuss in groups and report to the class.

Students will come to many different conclusions, such as: mom's clothes are longer than Xiaoming's; Xiaoming's clothes are shorter than his mother's; Dad's clothes are longer than Xiaoming's; Xiaoming's clothes are shorter than dad's; Mom's clothes are longer than Xiaoming's and shorter than Dad's. Dad's clothes are the longest, and Xiaoming's clothes are the shortest ... praise the group that can compare with various standards.

Conclusion: When comparing, be sure to determine who compares with whom. Different comparison standards will lead to different results.

4) Through the above study, can you find a comparable place?

Observe the situation map carefully, work in groups, find out the items to be compared and compare them. After the completion, each group communicates their conclusions in the whole class.

Summary: (Evaluate according to the situation of group cooperative learning. )

Through the above activities, students can experience, explore independently and learn cooperatively.

Third, knowledge consolidation.

Find out what can be compared between life and class. Find, compare and discuss it in groups.

Encourage students to observe carefully and speak their minds boldly.

Fourth, practice development activities.

Take out the prepared bouncy ball and table tennis, and compare which is bigger? Which is heavier?

Ask the students to guess the results first, then compare and weigh them in their hands to verify their guesses. The guessing and verifying methods of experiential mathematics inquiry.