Winter Shoe Box Diorama
Even though we haven't had any real snow yet, it's coming soon. In the meantime, have some fun with your kids by creating your own winter scene in a shoe box. It's not that difficult and with this site, they even give you printouts for the the sides, background and Dora characters if you want. You'll need to invest in a few craft supplies like pipe cleaners and styrene balls for the snowmen, and cones to make a tree, but you don't have to stop there. If you want to make one for Christmas, use old greeting cards for the background, and also, you can can use the cards for the seasonal images as well, such as Santa Claus, reindeer, pine trees and so on. In fact, while you're buying those items, see if there's anything else that might be fun to put into the scene. Cut out the images and glue small stands onto the back of them that you've cut from the greetings part of the card.
While the above site link is for 4 - 6 year olds, there are a number of sites that offer ideas for the older kids. Here's one that has some that are somewhat more sophisticated. http://www.stormthecastle.com/mainpages/dioramas/diorama-ideas.htm