For school I need to build a laser, preferably one that is quite strong and if possible can burn through duct tape. Can anyone suggest a model and instructions on how to make one.
You really need to use the search button, if you don't manage to understand how it works, than you more likely wont have the capacity to build a laser....
On this page just above the start of the thread is a long black bar with a white box, that says Google advanced search. Use that and all of your questions will be answered.
I suggest you start with eye safety.
Don't take this the wrong way I really am trying to help you.