We're invisible!

So yesterday it was Friday.
In art class we were doing masks. We had to lie on the desk and our partner had to put this liquid-white-bandage-thing on out face. Yasmin and I were smarter... We found a mask and instead of doing the design on someone else we did it on the mask in another room.
After school we decided to go to the auditorium. The projector and the computer were there this time. We connected both of them and logged on the computer. But the mouse wasn't working. I found a way to control the computer without the mouse and looked for a nice picture (of something not really... Yeah... Not telling you...). Suddenly the French section principal walked in. Everything was projected on the screen so I pressed alt+F4. He walked out the other door and didn't even notice us... Finally we found the right picture. We couldn't find a way to zoom in on it. Then another important member of the staff walked in. This time the alt+F4 didn't work... But he didn't notice us either!
We couldn't find a way to zoom in on the photo we found so we gave up and switched everything off. (Listen, I don't know how to clear the history without a mouse...)
After Simply my mum told me that Vasjok, my cousin, will not be coming to the summer campus this summer. I was really sad... What am I going to do?