The explanation of what a molecule is at the beginning is an option and could be missed. Simplify the count process for the second time of use. Make the program more friendly for children by having cartoon characters introduce the task. Needs to be fun, maybe a little man telling the information. Add sound to the screens for a commentary.
Extensions Extend the current program with a more advanced program as well as the present one.
If this included a double carbon bond and one or two additional elements, it would be possible to demonstrate geometric isomerism and optical isomerism. The screen could show mirror images for the latter. Add one extra atom -e.g. Something about polymers. Simple explanation of more complicated molecules would be a good idea.