Counting and Comparing

One and One #

One thing and one more makes two.

One thing and one more thing makes two things

Here is 1 square, all on its own.

Put 1 more square beside it: 1 + 1.

Push them together and count: 1 + 1 = 2!

Any two piles work the same way: push them together, then count them all.

Counting to Ten #

Every number is one more than the last.

Every number is one more than the number before it

This is a number line. Every number has its own spot, smallest first.

Drag the arrow. Every step right adds 1, and every step left takes 1 away.

Ordinal Numbers #

First, second, third — a place, not an amount.

An ordinal number names a place in a line: first, second, third

Five shapes stand in a line. Counting from the left, the circle is first.

Third names the triangle’s place in the line, not how many shapes there are.

The short way to write them: 1st, 2nd, 3rd, 4th — then 5th to 10th all end in th.

Writing Numbers to Twenty #

One numeral for every count, tens digit first.

Every count has one numeral that writes it down

Count the squares: 7. That count is written with one numeral, 7.

A full ten and 3 more. It is written 13: the 1 counts the ten, the 3 counts the rest.

Two full tens and nothing left over. That is written 20.

Number Bonds to Five #

The pairs that build five.

Five can be split into two smaller numbers in more than one way

Look at the circles: 5 is 4 + 1.

5 is also 3 + 2.

To find the missing part, take the whole − the part you know: 5 − 3 = 2.

More and Fewer #

Tell which group is bigger without counting.

You can tell which group is bigger without counting either one

Let’s compare two groups of squares.

Match each square with the one above it. 2 squares end up with no partner.

The longer row has 2 more. The shorter row has 2 fewer. Neither row was counted.

Longer and Shorter #

Line them up and see which reaches further.

Lining two things up at one end says which is longer without measuring

Lay them side by side, both starting at the same end. Now look at where each stops.

The ribbon reaches further, so the ribbon is longer and the string is shorter.

Same-size steps say how much: 6 steps against 4, so the ribbon is 2 steps longer.