Draw two cards from the deck and subtract the two numbers of the cards using a number line. Remember to use the biggest number first! Download this worksheet to help you with the counting back ...

2. Remember that when you use the counting-on strategy to think of the bigger number first. Count out aloud with Miss James as she jumps along the number line.

Let's look at another number line. Even if some of the numbers on a number line have been removed, you can still use it to estimate the value of a number.