This is a template to help draw graphs in case you don't have graph paper.  Something I wish I had when taking notes for my math classes.

Use the box template to draw the outline, then use a ruler or the optional slider to help draw in the lines. 

There are tick marks every .25" to help you get lines where they go, as well as a hole so you can clip it in your binder or whatever. 

I have not tested this at all, as I do not have a 3D printer available at the moment. I figure it will work best with a mechanical pencil so you can get your line sharp. Let me know if it needs adjustments, thanks.