Things I hear from professors about why their assignments don't work

The first in a series of "the things I hear from professors about why their assignments don't work":

Students are asked to generate ideas for a paper as a group. They don't have good ideas and they immediately go online to look for some. This frustrates the professor.

Students are asked to write a personal narrative. They go online and plagiarize someone else's personal narrative. Wierd, right?