Choose your bomb
Any bomb you pick runs a 5-minute classroom countdown to start. Change the length with one tap. Three bombs are free forever, and nine more are ready whenever you want the whole crew.
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 presets from 30 seconds to an hour.
Everything is classroom-friendly by design. Sound is off by default, so the timer never interrupts a lesson unless you want it to. A reduced-motion mode 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.
Get the full bomb collection
Three bombs are free forever. Want the whole crew? A one-time $4.99 unlock adds the other nine, yours to keep.
🔓 See the full collection