Lesson 4

Bouncing Ball

Est. Class Sessions: 4–5

Teacher Notes

If needed, copy the Centimeter and Inch Ruler Master.

Partners should agree on their measurements. If they do not, encourage them to work together to resolve any differences. Remind them what it means to measure to the nearest centimeter. If the line is between 7.5 cm and 8.5 cm, then the closest whole centimeter is 8 cm.

1. No, the lines are not the same length.
2. Yes, the measurements are the same. The line in Question 1A is a little more than 8 cm and the line in 1B is a little less, but the nearest centimeter for both lines is 8 cm.

1. Partners should agree within a tenth of a centimeter. Allowing for some error in copying the page and measurement error, accept 8.2–8.4 cm for A and 7.7–7.9 cm for B.

Ongoing Assessment

Use DPP item R to assess students' abilities to measure length in centimeters [E9].

1. Are the lines in Question 1 the same length? __________
2. Are your measurements the same? Why or why not?
1. Measure the line in Question 1A to the nearest tenth of a centimeter.
  Measurement: __________
2. Measure the line in Question 1B to the nearest tenth of a centimeter.
  Measurement: __________
3. Compare your measurements with a partner. Do you agree?
Measure the length and width of a sheet of paper to the nearest centimeter. Compare your measurements with a partner. Do you agree?

Length: __________ Width: __________
Measure the length and width of your Student Activity Book to the nearest centimeter. Compare your measurements with a partner. Do you agree?

Length: __________ Width: __________