What little kid doesn't love to dump their box of toys onto the floor? And what mom isn't driven crazy by this behavior because I know I sure am! Here is an activity that will keep your kids busy for hours that allows them to dump their toys to their hearts content without driving you up the wall in the process.
Hang a sand bucket from the ceiling on a string or yarn. Under it, put a box full of toys. Make sure to add lots of toys that start with the letter d like: dolphin, dog, dice, domino, dragon, dinosaur, dragonfly, etc. Have your child find all the things that start with a letter d and put them in the bucket.
When they have found them all, dump it out and start over again. After you have found all the letter d toys a couple of times, you can do other searches like all the land animals or all the nonliving things or all the things that are blue, etc. At the end, just let your child fill and dump to their hearts content with what ever toys they want.