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1st grade math · Unit 4: Counting and place value to 120

The end of a row

What this lesson shows

Fixes a mistake

After 39 comes 40, the next ten, not 30. Move to the start of the next row.

The worked example

The lesson works this one step by step: 39. Then your kid tries one like it on paper.

The steps

  1. 9 and 1 more make a ten
  2. The tens go up by one
  3. Then start the next row

Helping at home

After a number ending in 9, one more makes a new ten: 39, 40. After 40, the count goes on at the start of the next row, 41.

If your kid gets stuck

9 ones and 1 more make a new ten.

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

Standards

  • Common Core 1.NBT.A.1
    Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.
Matches a standard in all 50 states and DCSee each state's code

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