What would be some good ideas for a Periodic Table Themed Board Game?

For a science project I have to create a board game and every aspect about it has to be homemade (including the game pieces). For the actual board I decided to go with a periodic table theme, but since I have to create the game pieces I’m stuck on what to use/make. Also, I don’t know what to do for the instructions. As in, I am lost on what to do for the actual game play. What could even be the object of a game revolving around the periodic table? Please help. Thanks.