The Fifteen Puzzle is a classic numerical nightmare, originally introduced in 1880. Weve re-created it in smooth, polished metal and decorative enamel. To play, scramble the 15 numbered tiles in the tray, then try to slide them into correct numerical order. Having fun is great way to learn with ThinkFun & Think Fun games. ThinkFun games engage kids and educate kids. They challenge players and nurture the thinking skills important to growth and development. Our games aren’t designed to simply occupy a child’s time. They channel the natural joy and energy of play into a stimulating, family-focused way of building essential thinking skills.