MENTAL ADDITION

Add numbers entirely in your head using left-to-right and chunking tricks.

L4L5

CS.N.3.2·Using calculation techniques with numbers 0–10000(III)CS.N.4.2·Performing calculations with large natural numbers(IV)

Section 1 / 3

BREAK APART AND ADD IN STEPS

To add two numbers mentally, break the second number into tens and ones. Add the tens first (easy!), then add the ones. For 56 + 37: add 30 to get 86, then add 7 to get 93.

56 + 37 (in your head)

156 + 30 = 86

286 + 7 = 93

= 93

LEADER TIP

Start with two-digit + single-digit, then build up. The goal is fluency, not speed - accuracy first, pace follows naturally.

BEFORE THIS LESSON, TRY

Compensation Strategy

Friendly Numbers

PRACTICE WITH THESE GAMES

Math Sprint

Quick Calculate

Addition Quiz

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MENTAL ADDITION

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MENTAL ADDITION