As an example of how times have changed, my next-door neighbor built an amazing bong out of Aluminum pipe stock, (I'm guessing), in HS metal shop when we were kids. It was thick, w/ a knurled finish for grip and machined like it was made by Weissach. He got an "A" for the class w/ this as his big project. I often wonder whether he still has it, though my pot smoking days are long past.
Oh yeah, that was in 1972. Imagine the consequences of having a bong in HS now, with "zero tolerance" type policies.
The owner of the bong will be 49 y.o. this year, and he turned out fine, as did most all of his pothead friends.