Create your own fossils to display by using old coffee grounds. These work well as visual aids for science projects and makes a fun Earth Day craft for kids.
To reduce the drying time, bake the fosils for a short period of time to get the "dough" to harden.
Stir together the coffee grounds, cold coffee, flour, and salt until well mixed.
Knead the dough together and then flatten it out onto the waxed paper.
Use the can to cut out circles of the dough or use the dull knife to cut slabs large enough to fit your "fossil" objects.
Press your objects firmly into the dough.
When you take the object out, you have your "fossil". If you want to hang the fossil, poke holes into the edge to hold the string.
Let the fossil dry overnight (and up to two days) and then hang it if you wish.