A 60 minute lesson in which students will measure the area of plane shapes using informal square units.
This lesson contains a link to an external video. Please watch the video prior to presenting this lesson to ensure that the content is appropriate for your students.
Revise the content of the unit so far. Discuss which informal units have been used to measure area, which ones worked best and why. Lead the students to the concept that squares are best because they don’t leave gaps when placed together and because their sides are even (which gives more accurate measurements).