• Ask your child to use the counters to find some other hidden doubles. She may find 1 + 3, and 2 + 4 and 4 + 6 and 5 + 7 and 6 + 8 and 7 + 9 and 8 + 10 and 9 + 11 and 11 + 13. Write them down as she finds them. Some of these addition facts are hard to remember, but if you think of them as hidden doubles, they are easy.
  
  
• Look at all the hidden doubles you have written down. See if you can see the pattern. For example: 1 + 3. Look at the first number and count: 1, 2, 3. The middle number, the one you DON’T see in the question, is the number you double to get the answer. Another example is 4 + 6. Look at the smaller number and count up: 4, 5, 6. The middle number, the one you DON’T see in the question, is the number you double to get the answer.
  

Make a poster to show the hidden doubles.