*beep* You're teacher is not qualified to be a computer teacher. He need some serious electronics knowledge. I mean, I'm saying Mobo is build in with chips,transistor, etc. Mobo is a sensitive board which consists of transistors and some highly important chips that are very sensitive to high energy such touching of any chips prior to grounding yourself, water which contains chemicals which will disable some molecules and result into chips burnt out. There you will have to be a new mobo.
Vacuum it.....It will work fine, but also watch out to not break anything from the board.