Second grade math: Addition & subtraction within 20

This is a doubles fact - the same number added to itself. Picture two equal groups of 3.

Another double: think of 4 fingers on one hand-worth and 4 on the other.

A doubles fact, and 5+5 is a friendly "make ten" anchor you will reuse a lot.

Doubles again. If you already know 5+5, this is just two more.

A near-double: 6+7 is one more than the double 6+6. Find 6+6 first, then add 1.

Near-double: 7+8 is one more than 7+7. Double the 7, then add 1.

Near-double: 8+9 is one more than 8+8 (or one less than 9+9). Start from a double you know.

Near-double: 4+5 is one more than 4+4. What is the double, then one more?

Make a ten: 9 needs 1 more to reach 10. Take that 1 from the 8, then add what is left.

Make a ten: 7 needs 3 to reach 10. Split the 5 into 3 and 2, then add the leftover 2 to 10.

Make a ten: 9 needs 1 to reach 10. Take 1 from the 6, then add the rest to 10.

Think addition: 7 plus what makes 15? Or count back from 15 by 7.

Doubles in reverse: 9+9 makes 18, so 18 take away 9 is...?

Break it at ten: subtract 2 to land on 10 first, then subtract the other 3.

Doubles in reverse: 8+8 makes 16, so 16 take away 8 is...?

Start at 20, subtract 10 to reach 10, then subtract 1 more.