I agree, if you tell them what you actually do they'll be bored ;) Perhaps try to strike a balance between the cool stuff your company does (rockets, how can you go wrong there?), your importance to the company (our company depends on computers to keep rockets up in the air, i take care of those computers), and the usefulness of the job in general. If I were your kid I would want three things: 1) Don't embarass me 2) Make me seem slightly cooler 3) Don't embarass me. But hey, two out of three ain't bad ;) Above all lots of pictures.