jsbin.com: html, css and javascript web sandbox
template: basic html, css and js with event and output hooks into html via ids and getElementById()
basic DOM output: event function showing basic innerHTML and style property DOM manipulations of html elements
basic DOM output: event function loops and branches and then outputs via DOM manipulations
variables, types and arrays: 2 functions manipulate types and arrays and report via DOM manipulations
canvas: simple canvas with random colors using rgba and random rectangles
forms: valid, invalid, validation
jsFiddle