Ask the students if they know how many centimeters there are in one meter. Then you measure the height of one of the students. Say that the student is 1 meter and ... centimeters. You can also add this up together to know how many centimeters the student is. To do this, you have to know how many centimeters are in 1 meter. Then you can add the centimeters together. Using a visual aid, show how you can add meters and centimeters together. Explain that you can add meters and centimeters by first converting meters to centimeters, then adding them together. Have the students practice on their own using a visual aid. Afterwards you explain again how you can add meters and centimeters together by first converting meters to centimeters. To do this you take two jumps to the right, so you multiply by 100. Discuss a few problems with the class. Then the students must solve a problem, for which they can choose from a few possible answers or determine the answer by themselves. Next you explain that you can also convert to meters. You take two jumps to the left, so you divide by 100. Have the students solve a few problems on their own. Afterwards, you discuss addition of meters and centimeters in the form of a story problem. The story problem can be either a multiplication or a division problem. Have the students solve a story problem on their own.
To check whether students can add centimeters and meters together, you can ask the following questions:
- How do you add meters and centimeters together, when you have to give an answer in centimeters?
- How do you add meters and centimeters together, when you have to give an answer in meters?