Police replied with teargas as hooded youths threw bottles on the sidelines of a march by about 500 hundred high school students.
Police also used teargas against protesters in the western city of Rennes where nearly 2,000 high school and university students, and far-left activists, held a demonstration, a Reuters correspondent there reported.
In Paris, protesting students blocked the entrances, or staged election-related demonstrations, at about 20 high schools earlier on Thursday after student unions urged them to turn out.
"We are calling for action against far right candidate Marine Le Pen and the candidate of high finance, Emmanuel Macron," said UNL-SD student union leader Giuseppe Aviges, alluding to Macron's past as an investment banker.
(Reporting by Leigh Thomas and Helene Dauschy in Paris, Pierre-Henri Allain in Rennes, Editing by Richard Balmforth)