Convert between numbers, word form, and expanded form for multi-digit numbers. Compare them too.

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Do these Khan Academy exercises:

Next, give your students these challenges:

- 2020 Math Kangaroo Levels 1-2 Problem #21 by STEM4all
- Halving by NRICH

Conclude by leading this investigation:

Taipei 101 Foundations (multiplication, proof)

by MathPickle

4.NBT.A.2: Read and write multi-digit whole numbers using base-ten numerals, number names, and expanded form. Compare two multi-digit numbers based on meanings of the digits in each place, using >, =, and < symbols to record the results of comparisons.