Science Buddies: "Ask an Expert"

I'm new here but i was searching the web for help forums and found this site where everyone seems nice and friendly. After 3 weeks of doing nothing, I finally thought up of an experiment that relates to buoyancy and today my teacher tells me that my write-up is extremely shoddy. My project experiment is really simple (elementary level probably). I have to mold clay into different 4 shapes (each weighs 1.13kg) then put it in water and time how long it takes to sink. The time will be my quantative data although I'm not even sure if the clay will sink. Blah, I sure beated around the bush. Today, while criticizing my experiment (didn't really understand her b/c of her strong Chinise accent) she told me that i needed to find the density of my shapes. The problem is I don't know how and I dont think I have the proper materials to do so. Yeah, so what do I need to find the density of a cube/or a pyramid, rectangular prism, sphere, and cylinder and what materials do I need? For the density I think I got the formulas covered but I need some verification. ...Beated around the bush again. I really hate myself right now.

One topic per experiment please. See my reply in another post.

Density is simply a measure of how much stuff (mass) is in a particular area. To find the density of your objects, you need to mass them and find their volume. Then divide the mass by the volume to get the density. The standard units for density are grams per centimeter cubed. (g/cm3)