First of all, this isnt homework per se and i think i could get more useful help here than at /wsr.
Basically, i need to make a quick, 3 minute, science show about SIGHT and the eyes and whatnot. The target age group is around 12 yrs, but it should be interesting and have some sort of wow factor for people of all ages and education levels. One of the biggest problems right now is that i want to include some sort of optical illusion (with mirrors for example) which would fool a small auditorium of people. How could i do this? Simply placing mirrors would make people sitting in different places see a different thing. Any other ideas or recommendations would be greatly appreciated (good models for the eyelens(can be contracted and streched), maybe even some experiments(havent been able to think of any relating to this topic yet))

Thanks a lot, hope you have a great day even if you cant help.
Best wishes from Estonia