Addition is a lot like counting.

1.  If you had 1 fish sticker:

Then a friend gave you 1 more fish sticker:

You would have 2 fish stickers:

The math for this would be: 1 + 1 = 2

2.  If you got 3 more stickers for doing a chore:

You would add 3 to the 2 fish stickers you already have, so you would have 5 fish stickers:

The math for this would be: 2 + 3 = 5

3.  If you bought 2 more stickers from your allowance:

 

That would add 2 stickers to the 5 stickers you already had, so you would have 7 stickers:

The math would be 5 + 2 = 7

4.  If one of your birthday cards had 3 stickers in it:

Then you would add 3 stickers to your 7 stickers, so you would have 10 stickers:

The math would be 7 + 3 = 10

Here is a page that just shows the 10 fish. You can print them and use them to play with addition if you want.

Here is a page that just shows the 10 fish outlines so you can color them in. You can print them and use them to play with addition if you want.