Pick a bomb for your classroom timer
Any bomb you pick runs a 5-minute classroom countdown to start. Change the length with one tap. 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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Other timer lengths
A good classroom timer does one thing a wall clock cannot: it makes time visible. This free countdown timer for the classroom puts a big, friendly cartoon bomb on the smartboard, with digits readable from the back row and a fuse that shows exactly how much time is left, no time-telling skills required.
It covers the everyday routines: a cleanup race before pack-up, a two-minute transition between activities, per-question quiz countdowns, center rotations, and timed writing sprints. Pick a length below, or use the timer’s presets from 30 seconds to 10 minutes and Custom for any time up to an hour.
Everything is classroom-friendly by design. The speaker button switches the sound between Off, Soft and Loud, and the timer remembers your choice, so a quiet room stays quiet. A Motion switch in Settings calms the animation for sensitive rooms. There is no sign-up, nothing to install, and it works on any smartboard, projector, laptop, or tablet.
Want the research and routines behind it? Our classroom timer tips for teachers page covers visual timers for ADHD, the transition-time study that saved teachers 39 minutes a week, and ready-made timer routines you can start tomorrow.
From teachers using it in class
FROM: BRAZIL
“For my students. I’ll get through things faster”
“Pra meus alunos, farei mais rápido” (translated from Portuguese)
FROM: BRAZIL
“So my students have a few minutes to do their work. This app is really good! Congratulations on the app!”
“Para meus alunos terem alguns minutos para fazer seu dever, mas esse app é muito bom! Parabéns pelo app!” (translated from Portuguese)