The 31-year-old assistant is said to have been attacked with a knife in connection with a bag check.
French President Emmanuel Macron condemns what he calls a "meaningless wave of violence" after the incident.
"The nation mourns and the government has been mobilized to reduce crime," he writes on X.
Over the past few years, French schools have been plagued by a long series of attacks on teachers and students.
In March, schools in the country were allowed to conduct random checks in search of knives and other weapons on and around schools. At the end of April, after a fatal attack on a school in Nantes, the education ministry said that nearly 100 knives had been found in school checks across the country so far.
