I had trouble when I began teaching with time management. I would get so
involved in the project with the kids that I would forgot to keep my eyes on the
clock. So, I went to the dollar store and bought a cheap-o spin dial "ding"
timer. It goes up to 60 min, never needs batteries. I spin the timer as we
get started working in class and set it to when we need to start cleaning up.
The students are trained now (think Pavlov's dog ;-) that when they hear the
ding, they need to start cleaning up their own area. Simple solution that was
effective for me.