This hands on lab helps students learn how covalent bonds form through not only drawing them but also making them.
For each molecule, the student has to prove how it is made through the sharing of the different valence electrons, and then make it with a basic model kit (not provided). You could also use mini marshmallows and spaghetti instead of a model kit to make the molecules.
Students must also get signed off to prove their knowledge before they move onto the next problem.
I have seen HUGE gains in the understanding of covalent bonds from this simple and fun activity.