This is a cool project that starts to expand further away from turning on and off LEDs. With the LED array setup, you can introduce new wiring/soldering practices based on knowledge of series and parallel circuits plus learn some of the magic with programming to control the LED array!
Nice potnetiometer knob published by Truefawkes
found at: https://www.thingiverse.com/thing:2247667
Mount 3D printed parts onto 3DLS platform, wire, and then load and test program.