Virginia SOL Math / Grade 2 / Number & Number Sense

2.NS.3

Odd, Even & Ordinal Numbers

What you'll learn

  • Tell whether a number to 99 is even or odd
  • Use ordinal numbers from first through twentieth
  • Group and count objects to decide even or odd

Words to know

Even —
a number that can be split into two equal groups, ending in 0, 2, 4, 6, or 8
Odd —
a number that leaves one left over, ending in 1, 3, 5, 7, or 9
Ordinal number —
a number that tells position, like first or third
Pair —
a group of two

Why it matters Knowing even and odd helps us share things fairly, and ordinal numbers help us describe order, like who came in first.

Worked examples

Model ItI do

Is 14 even or odd?

Try to make pairs from 14. Seven pairs of 2 make 14 with none left over, so 14 is even. Also, 14 ends in 4, and numbers ending in 0, 2, 4, 6, or 8 are even.

Try It TogetherWe do

In a line of children, which child is the fifth in line?

Count from the front: first, second, third, fourth, fifth. The fifth child is the one in the fifth spot from the front of the line.

Now YouYou do

Is 27 even or odd?

Look at the ones digit to decide. Check your answer in the back of this chapter.

Practice

Mastered 0 of 11

Warm-up

Ease in with the basics.

  1. 1.Is 6 even or odd?

  2. 2.Is 5 even or odd?

  3. 3.Who is the first person in a line, the one at the very front or the very back?

On Level

The core Quick Check from the book.

  1. 1.Is 30 even or odd?

  2. 2.Is 19 even or odd?

  3. 3.Which day is it if it is the third day of the week starting with Sunday?

  4. 4.Name the ordinal number for position 10.

  5. 5.Circle the even number: 7, 12, 15.

Challenge

Stretch your thinking.

  1. 1.Is 88 even or odd?

  2. 2.Name the ordinal number for position 15.

  3. 3.There are 20 children in line. What ordinal number names the last child?