Odd and even numbers · Grade 1

In Grade 1 you learn: odd and even numbers to 20.

Even numbers can be shared into pairs (or two equal groups) with nothing left over. Odd numbers always have one left over. You can tell straight away from the last digit, which makes odd and even a quick check on lots of calculations.

Key facts

• Even numbers end in 0, 2, 4, 6 or 8. Odd numbers end in 1, 3, 5, 7 or 9.
• even + even = even; odd + odd = even; odd + even = odd.
• even × anything = even; odd × odd = odd.
• Counting in 2s from 0 gives the even numbers; from 1 gives the odd numbers.

Worked examples

Other years

• Odd and even numbers · Grade R
• Odd and even numbers · Grade 2