Pick a bomb for your transition timer
Every bomb runs a 2-minute transition countdown. Pick a preset or set your own time. Round Buddy is free to play. Unlock all 50+ bombs and 140+ worlds for $4.99 with no ads. Every bomb is unique! Watch for different animations, sounds, and explosions.
For home
Unlock all 50+ bombs and 140+ worlds
Every bomb is unique, with lots of different booms, and you can put any bomb in any of 140+ animated worlds. Pay once, use on up to 5 devices. Removes all outside ads from this site.
For teachers
Classroom license
Every bomb and every world on up to 30 school devices, for one payment.
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Smoother classroom transitions
Transitions add up fast, and a visible countdown helps. In one classroom study (Ardoin et al., 2015), on-screen transition timers cut transition time by 67% and gave teachers back about 39 minutes of instruction a week. Put the transition timer on the board, give a two-minute warning to switch activities, and let the class race the fuse.
Two minutes fits most quick moves: packing up, switching stations, lining up at the door. Use 3 to 5 minutes for bigger transitions, or tap Custom for any length.
Pair it with the cleanup timer at the end of the day, or open the 2 minute bomb timer for the same length from any page. The classroom timer runs the bombs on the smartboard with no ads on the page, and our teacher tips cover more cleanup and transition routines.