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2nd grade math · Unit 9: Shapes and perimeter

Count each unit once

What this lesson shows

Fixes a mistake

Tick each unit as you count around. Then no unit is counted twice.

The worked example

The lesson works this one step by step: 4 by 2. Then your kid tries one like it on paper.

The steps

  1. Start at a corner
  2. Tick as you count
  3. Stop back at the start

Helping at home

Start at a corner. Put a tick on each unit as you count it. When you are back at the start, stop: every unit has exactly one tick.

If your kid gets stuck

Tick each unit once.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

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