User Drawing Overlay In Storyline

I've gone through a few previous posts giving the user the ability to draw over other objects in storyline, but none have really met what I'm trying to do.

I have a project for a meteorology course and the faculty member wants students to be able to let students draw and color in maps they provide without having to download a PDF and edit it in Paint program.

Does anyone have a solution for either integrating a JavaScript Canvas overlay (not sure how this works, tried some tutorials) in Storyline or a Web Object maybe that would let the user draw over other images placed in Storyline? Even a website that lets me save a specific image in drawing software and then insert that as a WebObject students could then draw over would be helpful.