This timer can be put on your board during center time so students can see exactly how long they have left to complete their center. Students will be warned when there is just 30 seconds left so they can start cleaning up and getting reading to move. The last slide is timed for a minute as well and I usually find one minute theme songs to put in it (a different one each month). Students enjoy listening to the music as they transition to their next station.
Note: If you want shorter station time, just delete slides.
You have to put in your own music to the last slide because it won't work unless the song is downloaded on your computer.