We made gingerbread cookies for the first time. It was a lot of fun to work with the boys on a project. The best part was the shapes. We only had some random cookie cutters so we made Christmas pumpkins, shamrocks and jalapenos. You haven't lived till you had a gingerbread jalapeno. Two cans of butter cream frosting later and we had way too many cookies. Of course we ate them anyway.
Being a smartass I had to make a gingerbread Stone Henge. It collapsed under it's own weight. I would have made a lousy druid.
Then for science we did experiments with dry ice. We needed about 2 ounces but the minimum brick was 5 lbs. So we put dry ice everywhere. It was like a bad 50's sci-fi movie. We even tried to blow up a bottle of water. It didn't work, but it thoroughly carbonated the water.