How can you not want to make Jello Brains? Even without children, it is such a fun Halloween treat that it should find its way onto everyone's table at least once. Halloween is the perfect excuse to make creepy and delicious things.
Kraft has a free eBook of recipes, showing how to make all things Halloween. Most of the recipes use Jello, and some creativity. The finished foods will please all your little ghosts and goblins at the table.
I also found a cute video about how to make a Jello brain on Youtube. Be warned, if you are sitting with a little goblin and searching, MOST of the videos will be extremely inappropriate for younger kids.