If you are looking for a project that your kids can actually do by themselves, then you should check out Eye Can Art.  Madison and I recently tried out their Printmaking Kit, and we both loved it.  The age on the Printmaking Kit is four and up, and I was impressed that it really was aged appropriately.  With only a little help from me, Madison and I were able to make her print (she chose to make a picture of herself).  I also love that everything (and I mean everything) you need comes in with the pack.  It even comes with the glue stick and the scissors we needed!  Here is everything that comes in the kit:

The first thing you do with this kit is decide what you want to make a print of.  Madison decided she wanted to do her face. After you cut out the shapes of your face, you then glue them on the face, and take some paint and roll it over.

After we covered the face in paint, we quickly put it another piece of paper and pressed it down hard (using the roller).  We added the second paint color to give the face a blue border.

As you can see, Madison was able to do each step herself.  Here is the finished product:

This took us about an hour to complete, and I highly recommend this as a gift or just a craft to do around the house.  There are enough supplies to make several prints, so Madison is looking forward to her next project.  I will definitely be buying more Eye Can Art kits.