'Lights Out' is a classic game of logic. You have a five-by-five grid of cells. Clicking a cell changes its state, along with its (up to four) neighbours.
In the original Lights Out game, you start with all the cells on, and have to turn them all off. In this version, you have twelve target patterns to try and recreate.
See [url=http://www.geogebratube.org/material/show/id/1256]this Geogebra sketch[/url] if you just want a Lights Out board to play with.
