Although it is not strictly natural science the mechanics of catapults seemed a natural fit and as in the first week of science camp creation caused a lot of concern about their fingers but once the first ball was launched on one seemed concerned about anything except how far their ball would go and who they could hit with it. Check out the video: catapults1 and catapults 2
Paper making is messy but is something not very many kids have done. I started with cardboard egg cartons and ground them in the blender before class to create the pulp. We talked about use of deckles (the frame for straining the paper) and the process to press the water out and turn out a page of paper with bits of paper or shred in the surface. We did not dye the paper this time although we have in the past.
It takes a day or so to set up well enough to unearth the fossils from the sand. We used large tubs to support the castings and catch the sand. They brushed off sand with stiff brushes until they could see their cast fossil copy then let it dry a bit more and rebrushed. Once the sand was off the results were pretty amazing--the kids were picking out things on the surface that they recognized from the pressing part and were pretty impressed.
Constructing a volcano from a juice bottle is easy using rigid wrap and newspaper. Everyone shaped one and set it out to dry. On Thursday they
just looked too white to this group so everyone painted theirs before the eruption. (click on picture to view) From art camp 2012
The results were satisfying but more to come on that as we invite the younger kids to the eruption.