This is an open-ended educational tool that you could use as a math center to help students visualize number sequences and model strategies for addition, subtraction, multiplication and division.
First students should choose the type of number line they wish to use:
Then they could use flashcards or some sort of prepared equations to solve using this app. One way to solve is simply using the pen tool to write and draw the jumps on their number line:
If you want your students to show you their work, simply have them write or type their name somewhere in the white space and take a screen shot of their work by pressing the power button and the home button at the same time. You can retrieve their work by going into the Camera Roll to see how they solved their problems. These pictures can be pulled off of the iPad by putting them into DropBox or Google Drive.
Another FREE app that is a great tool for checking math work is yHomework.
Maya's Fractions from Julie on Vimeo.