We have this game called "Beat the Clock". We have one of these kitchen timers that you turn to the desired cooking time and that turns back to a big "ding" when time is up. So here is how it works: we set the timer to approximatevly 5 minutes (but use whatever amount of time is appropriate for your own kids) and then we go "1...2...3.... Lets' Beat the Clock". Kids love it, abd they lear to tidy up their toys and stuff...
LOL! Probably not... unless there was a really motivating reward if they do beat the clock... but in that case, you probably don't even need the "clock" trick :-)
i just posted this comment in another spot. i also have the children each pick up all the toys of one color. ie, john picks up all the blue toys, lisa picks up all the red toys, etc.