Start with a simple HTML template called with 'theirname.html'. Add a JS loader: <script src="theirname.js"></script>. Load that page in browser; bookmark it.

Start with a simple HTML template called with 'theirname.html'. Add a JS loader: <script src="theirname.js"></script>. Load that page in browser; bookmark it. (Easy access!) Now whatever they edit into theirname.js will 'run' when they reload the page. e.g. alert('Hello World!') When they're ready to add an image, time to learn a little HTML ;-O