I think sometimes it is useful to have the facility for a countdown timer in the classroom for various activities ranging from tidying up to a fixed time for completing a piece of work. I want to feature a couple of timers which I think work well on an interactive whiteboard.
The first Supertimer is the free, cut-down version of a timer which you can buy that has more features. On this version there isn't the facility for turning off or changing the music but you can get round that by turning the volume down on your computer.
The other timer program which is called Egg Timer doesn't have sound during the countdown period so you simply set it to your required time limit as explained on the Home page.