Here's a new version of this SmartBoard activity: the idea is to teach subtraction skills by "jumping" from one number to another number through smaller steps. Press the button and two numbers will appear in each box on the number line. Your kids can grab one of the little figures on the size and show the different "jumps" and label their size to get from one number to another, which shows their "difference" better know as the answer to a Subtraction problem!
Check this out - it's free! What do you have to lose? I think it will also work on other formats, including ActivBoards and other products. Please let me know what you think of it by leaving me a personal message - hey, it took me a couple of hours to get this right, so would it kill you to spend a few minutes telling me what you thought of it?