Teaching purpose:

1 Through activities such as "walking", "estimating" and "thinking", we experienced the length of 1 km, and initially established the spatial representation of km.

Make students know 1 km = 1000 m, learn the simple conversion between km and m, cultivate students' observation and practical ability, develop students' spatial imagination ability and infiltrate ideological education in time.

Teaching focus: Experience how long 1 km is.

Difficulties in teaching form a perceptual knowledge of how long a thousand meters is through experience activities.

Teaching preparation: meter ruler and meter teaching time:

teaching process

First, the activity import.

Students, do you know how long it will take you to take a step? Students may not remember it for a while, it doesn't matter. Please choose one student from each group to step forward and ask another student to measure. Don't you know?

Step 2: Play middle school.

1. Take a walk. Through the actual measurement, feel how long it takes to walk 100 meters. Please walk around the playground in groups, count how many steps there are in10m and100m, and how much time they spent respectively, and make records. Back to the classroom, let the students report their step test results first and talk about their feelings after walking 100 meters.

2. make an estimate. Through the students' personal experience just now, I guess and think about the length of 1 km.

(1) Just now we measured how many steps there are in 100 meters. Thinking: The length of several 100 meters is exactly 1 km. (2) How many steps does it take to walk 1000m?

(3) The courseware shows that the playground of our school is 200 meters. The length of the circle along the playground is exactly 1 km. Think about it: How many minutes did it take us to walk around the playground? (2 minutes) Then walk five times along the playground, which means how many minutes does it take to walk 1 km?

3. Think about it. Further experience how long 1 km is.

(1) You must be familiar with Zhongjie, right? Please see the courseware: Daoguang Road Cinema, Commercial City, New Mart and Wal-Mart are about 1 km away from the Cultural Building.

Please close your eyes. Let's walk along the middle street in our mind and feel the actual length of 1 km. Summary:1km =1000 m.

Step 4 read it. Reveal the relationship between kilometers and meters.

(1)1km =1000 m, which sounds difficult to distinguish. Reading aloud in Chinese class pays attention to cadence. Who can skillfully use pause to distinguish between kilometers and meters, so that you can understand at will? 1 (pause) km = 1000 (pause) m guidance reading: pay attention to the appropriate pause between numbers and units.

(2) Explanation: Kilometers, also called kilometers, can be represented by the letter km. Think about it, how is the relationship between kilometers and meters expressed in letters? Named board performance

5. Fill it out. Feel the application of kilometers in daily life.

(1) We know how long 1 km is and how long it takes to walk 1 km by different means of transportation. Look at the picture and choose the right answer. Fill in the complete number on page 42.

(2) (Courseware display) Please look at some shots taken by the teacher on the way from school to Zhongjie on Sunday. Please observe carefully. Where is the "kilometer"?

I. Roadside milestones

Two. Motorcycle trailer speedometer

Three. speed limit sign

Four. There are students' answers on the guide signs, and the pictures are displayed on the screen respectively.

Summary: Kilometers are often used to measure long distances.

6. make an estimate.

(1) We know the actual length of 1 km. Now please estimate the place about 1 km away from the school gate. Who can prove it in a more scientific way? Students express their personal views.

(2) Teacher's summary: 1 km, we walk about 2000 steps. We can count 2000 steps from the school gate and see where you have just walked. Is it consistent with your estimate just now? 3. Learn by doing: Complete questions 1 and 2 on page 43.