Create your own Pixel Art Paint Program, which lets you choose colors from a palette of your choice to "paint" pixel art. The interface is completely up to you, but it could look something like this:
1. Create 10 or so small, white, square divs to start making a pixel canvas.
2. Add an event listener to each so that when clicked on, that div's background turns red.
3. Add a couple more square divs to make a palette. Begin with 2 background colors (red and blue), which allow the user to set the current "brush" color, instead of a pixel's background always turning red.
4. Add the rest of the standard colors to your palette as well as an eraser. (Red, Orange, Yellow, Green, Blue, Purple, Black, Brown, White, etc.)
5. Add more divs to expand the size of your pixel canvas.