Henry has a strong concept of number and can order numbers up to about 15 with confidence. He has been working on consolidating his knowledge of numbers in the teens, including their sequences and how they are pronounced. Here he is working with Denzil to decide what numbers come before and after a given number in the teens. This is an example of his best work because he challenged himself with enthusiasm to explore accurate sequences of numbers beyond 15. The boys used the 0 to 20 Number Line when they needed it for support.