winners of the 3 prisoner challenge

Congratulations to Eden in the 3rd grade, Harlan in the 4th grade, Roberto, Jonah, and Cole in the 7th grades for finding a reliable strategy. Harlan suggests, prisoners one and two will turn an on light off one time each. Prisoner 3 will turn an off light on. The second time he sees it off, he knows that all 3 prisoners have visited the room!