Measuring Length with Paper Clips, Cubes, and Blocks

Look for this idea outside of your lessons. Before rulers existed, people measured with feet, hands, and grain lengths. The idea has not changed at all. This is worth learning because a measurement without a unit is not a measurement at all.

Watch for it today, and when you spot it, tell someone what you noticed and how you knew. Ask yourself where else the same idea might be hiding, then go and look.

Let us think about this slowly. You do not need a ruler to measure. Lay paper clips end to end along a pencil and count them: six paper clips long. Cubes and blocks work the same way.

Whatever you use is called your unit. Say the number and the unit together, because six alone means nothing. Six paper clips tells someone the whole story, and they could check your work themselves.

Watch out for units that are not all the same size. If you measure with mixed paper clips, some large and some small, your count means nothing. Every unit in one measurement must be identical to the others. Show your work to someone and explain it in your own words.