Arrange students to walk in groups on the playground, count how many steps it takes to walk10m and100m, and how long it takes to walk100m, and make records, and communicate the feelings after walking100m in groups.

Activity 2: Indoor

(1) Students report the exchange results. It takes time to walk 100 meters.

(2) Let students imagine how many steps and how long it will take to communicate in the group.

(3) The group reports the estimated results and methods.

Finally, let the students talk about 1 km in life. The estimated distance from home to school is 1 km?

Teaching reflection

Teaching is divided into two stages. The first stage is conducted outdoors, so that students can actually walk the distances of 10 m and 100 m in groups, and communicate the number of steps taken, the time spent and the feelings after walking in groups, paving the way for breaking through the key points. The second stage is held indoors. Through group communication, students can imagine the length of 100 meters and walk 65,430 meters. Break through the key points. Finally, through practice, fully expand the depth and breadth of knowledge, develop students' spatial imagination, and consolidate students' perceptual knowledge of how long 1 km is formed. This practice not only stimulates students' interest, but also permeates the mathematical thinking method of guessing, which is a valuable and interesting practical activity.