Grade 2 › G2U08 Measuring Length

Grade 2 › G2U08 Measuring Length › L2
GRADE 2 · ALBERTAOUTCOME AB-G2-2M1

L2 · Same length, different units

Learning goal

“I can explain why the same length gives different counts in different units: the bigger the unit, the fewer copies I need.”

Compare — to look at two measures and say how they are the same or different.
Bigger unit — a unit that covers more length with each copy, so fewer copies are needed.
Smaller unit — a unit that covers less length with each copy, so more copies are needed.
Worked example

We measure the same desk two ways. Step 1 - LONG PENCILS: the desk is 4 long pencils long. Step 2 - SHORT CRAYONS: the same desk is 8 short crayons long. Step 3 - COMPARE: the desk did not change. The unit changed. Each long pencil covers more length, so fewer pencils are needed. Each crayon covers less, so more are needed. Say it plainly: for the same length, a bigger unit gives a smaller count, and a smaller unit gives a bigger count.

Check yourself — explain it

The desk is 4 pencils long and 8 crayons long. Why are the counts different?

Paired problem — example still visible

A shelf is 5 big books long. The same shelf is 10 little books long. Which book is the bigger unit? -> the big books (fewer copies needed)

Faded completion — last step is yours

"A rope is 3 arm lengths long and 12 clips long. The ___ unit is bigger, because it needs fewer copies." -> arm length

Ready to practise?

10 scored questions with a 3-rung hint ladder. Mastery needs 8/10 plus both gate questions.

Start practice →Take the unit quiz