The Halloween massacre

The Halloween massacre is one of the most famous college myths of all time. It is not certain how and when it actually started, but it has made its way into most American universities. For decades now, it has created panic and fear among thousands of students (and possibly even a few professors as well). 

The legend goes that a popular psychic has made a prediction that on a Halloween night a masked man (in some variations, he is dressed as Little Bo Peep) will enter the campus of a university that starts with the letter 'M' or 'W' and is located near a pond/lake/river, railroad track, or cemetery. He will then kill everybody there. This story has existed for many years now, but no massacre has happened yet. 

However, students from all around the country still fear it, especially at colleges such as the University of Michigan, Michigan State University, the University of Minnesota and the University of Wisconsin.

Source: www.topuniversities.com

Secret tunnels below the campus

Lots of universities in the world are believed to have secret tunnels below their campuses. Through the years, students have made up various stories concerning hidden pathways leading to dungeons, ritual rooms and so on. 

This legend is again particularly popular in the US. Students from Michigan State University believe that there are creepy dungeons below the university. That is partially true, because there ARE tunnels running under the campus, but they are actually steam tunnels that were built to house campus utilities. No dungeons whatsoever have been found. 
Another version of the same belief exists at the University of Illinois at Urbana-Champaign, where some students there believe there is a secret room below the Foreign Language Building and that it holds a supercomputer, which is owned by the government. 
They also claim that there are secret tunnels below the buildings on the Quad, whose origin and purpose is unknown.
Source: https://www.topuniversities.com/