The Junk Drawer
For kids, cleaning out junk drawers is a bit like discovering treasure. Have them start by separating and putting like objects together in piles. For the pens and markers, give them a piece of scratch paper to write on. If the writing utensil doesn't work, chunk it.
Finally, grab some dividers and small baskets from the dollar store, and let the kids rearrange the items back inside. Not only will that be one less item on your To Do list, but it will have kept them occupied for a while. Please be warned you will be interrupted several times with amazed "Ooh! Look at this!" and "Look what I found!" comments, as well as curious "Mom, what's this for?" and "Can I have this?" remarks.
(Additional hint: this type of activity works best on a bad weather day, when they can't go outside to play.)