The kids and I made stupid sock creatures for my niece and nephew. Those weren't hard to make, but they were time consuming.
I've been at a loss as to what my mother-in-law would like, but finally I remembered something I saw a link to a while back. I'd tell you where if I could remember, but I don't. It was a tutorial on making silhouettes. Now a real silhouette is done with someone snipping away freehand, and it is really cool to watch. This is not that way, but rather something that requires no real artistic talent.
First, I took a photo of each of the kids' profiles up against a blank wall. Okay, first, I really went to Michael's bought a picture frame with a matte (my supply of millions of them being packed up, of course) and a piece of black cardstock. Then I took pictures of the kidlets. Getting a one year old to turn sideways long enough for me to snap a picture was hard, but it turned out to be harder to get a three year old to do it. Once uploaded on to the computer, I cut each of their heads out using the magnetic lasso tool, sized them to all be approximately the same, and printed them out.
The pictures I then cut out, turned upside down, traced them with a pencil on the back of the black cardstock, cut them out, glued the silhouettes to decorative acid-free cardstock that I already had lying around, (alright, I actually stole it from the kids' art supplies) wrote each child's name and the year under their silhouette, taped the pictures onto the matte, and put the picture frame back together.
Originally, I had planned to get the kids to paint some sort of watercolor for the background behind their heads, but using the cardstock made the whole thing go a lot faster and I realized I didn't really want to give my one year old access to watercolors.
So here's the result. I think my mother-in-law will enjoy it.