1, so that students can perceive and understand the meaning of kilometers in specific life situations, and initially establish the concept of the length of 1 kilometer.

2. Knowing 1 km = 1000 m, simple conversion between length units can be carried out.

3. Experience the measured process, feel the close connection between mathematics and life, and be concerned and curious about the length of things around you. I can actively participate in the measurement and experience the fun of math learning.

Teaching emphases and difficulties:

Key point: the establishment of the concept of kilometer length.

Difficulties: conversion and estimation between length units.

Teaching preparation:

Multimedia courseware, CD-ROM, ruler, tape measure, etc.

Perception of "kilometer"

(1) guess.

Dialogue: In order to show his skill, the Monkey King changed the golden hoop to 1km. Observe the picture carefully. The courseware shows the situation map. ) Can you tell me how long 1km is from the information provided in the picture?

Courseware demonstration: Sweet sitting in a hydrogen balloon is as high as the Monkey King's golden hoop, which is 1000m, so 1km = 1000m).

(2) Feel the "kilometer".

It takes about 1 m for a person to spread his arms, and 1 km for about 1 0,000 students to hold hands.

(Guide students to understand the actual length of 1Km with the help of the measurement unit "m", and know that 1Km is 1000m, and km is also called km, which means 1km = 1000m).

(3) Dialogue: Do you feel deja vu when you see "Km"? Where have you seen it?

(There are pictures of milestones along the road in the courseware) It seems that a long distance is usually calculated in kilometers.

(4) Summarize the law

We know that 1 km = 1000 m, so what is 2 km? What about 4 kilometers? What about 9 kilometers?

(4) Summary

What did we learn in this class? The title of the health teacher's blackboard writing.

Dialogue: Millimeter, centimeter, decimeter, meter and kilometer are all units for measuring the length of an object, which are called length units.

Can you arrange them in a certain order?

The students answered, and the teacher wrote on the blackboard.

We have learned these length units, so how to choose the length unit when measuring the length of an object?

Design intention: By sorting out the learned length units, let students choose the appropriate length units according to their own understanding, and cultivate students' logical ability.

Activity 3: Talk about harvest.

What did you learn from this course?