You need:plastic tube,paper cup,aluminium foil,tape,glue
Make hole in the bottom of the cup and cut out
a circle about the same size as the size of the plastic tube. tear off a piece of aluminum foil and roll it around the tube,
taping it down at the ends.Fit the plastic tube into the
hole at the bottom of the paper cup, and reinforce it with some glue.
your stesthoscope is ready