Teaching content of 1: understanding numbers within 38-40 pages of the textbook 100-the order and comparative size of numbers.
Teaching objectives:
1, knowledge goal: initially grasp the numerical order within 100. Initially, the sizes of numbers within 100 are compared.
2. Ability goal: Make students feel the meaning of numbers within 100 by preliminarily combining specific things, and express things in daily life with numbers within 100, and make simple estimation and communication.
3. Emotions, attitudes and values: Learn how to express size in your own language. Teaching focus:
1, and initially grasp the numerical order within 100.
2. Preliminary comparison of the size of numbers within 100. Teaching difficulties:
1, understand the meaning of numbers and master the number order within 100.
2. Explore the arrangement of percentiles. Teaching aid preparation: courseware.
Teaching process: (1) Review:
1, counting: count down from 100 to 502. See if the counter compares the numbers within 20. The teacher dials, says and compares the sizes of the two numbers, and explains the reasons. "What do you think?" Thinking: Let's start with ten places. The number in the tenth place is large, and this two-digit number is large. If the ten-digit numbers are the same, look at the one-digit numbers. If the one-digit number is large, then the two-digit number is also large.
(2) Newly awarded: 1, teaching example 7:
(1) Teachers show slides (hundreds of numbers) (2) Students observe and discuss, "What are the characteristics of the arrangement of these numbers in the table?" The teacher gave examples to illustrate the characteristics of guiding students to look horizontally, vertically and obliquely. (blackboard writing: horizontal, vertical and oblique) Features:
① The number of five in the first row is even, and the number of five in the second row is odd.
② The number of digits on the diagonal from the upper left to the lower right is the same as the ten digits.
③ In the next line from the top right to the bottom left (except 10), the number in the tenth digit gradually increases from 1 to 9, while the number in the single digit gradually decreases from 9 to 1.
(3) Students begin to fill in the form independently.
(4) Look again, what are the characteristics of this numerical sequence table?
2. Exercise: The teacher asks questions and the students answer them quickly. For example, "What is the number 8 in the fourth line?" 3. Color the designated number according to the requirements on page 38. What new rules did the four-person group discussion find? 3, than the size.
(1) The number ratio of ten digits is the same. The courseware shows the counter. Students say the numbers on the counter respectively, then compare the sizes, say the methods of comparing the sizes, and the teacher summarizes the methods.
(2) The number ratio of ten digits is different. The courseware shows the counter. Students say the numbers on the counter respectively, then compare the sizes, say the methods of comparing the sizes, and the teacher summarizes the methods.
(3) practice. The courseware shows exercises, and students practice and talk about the methods of comparing sizes.