Protests marked the start of a new academic year in Egypt with several students being arrested for demonstrating against the army-backed government.
Sunday's rallies were held to protest against restrictions on political as well as campus freedoms, besides the return of military rule.
The military-backed government has been in power since the July 3 coup that ousted President Mohamed Morsi.
"Down, down with military rule," an estimated 1,500-2,000 students chanted at the Cairo University campus.
Al Jazeera's correspondent in Cairo, whom we are not naming for security reasons, said the protests were "very widespread" in cities including Suez, Alexandria, Fayyom, and at several universities in Cairo, greater Cairo and Giza.
"It's significant because it's the first time we've seen university campuses [used as venues for] anti-coup protests," our correspondent said, adding that more protests were expected to "be held for a few hours every morning".
Egyptian universities have a history of a strong Muslim Brotherhood presence and Egypt’s youth has been at the forefront of the revolutionary movement since former President Hosni Mubarak was toppled in 2011.
An estimated 700,000-750,000 new students join universities every year in Egypt.
Seventeen-year-old student Sarah Adel Ibrahim was handed to authorities by residents of El-Menoufia, a town in the Nile Delta, after she wrote "down with military rule" on the walls of a school, the state-run Al-Ahram news website said.
Two high school students were also arrested in the city of Marsa Matrouh for distributing flyers calling on students to boycott school in protest of the coup, according to a security source.
Follow our ongoing coverage of the political crisis in Egypt
"The two students were caught distributing flyers accusing the army and police of being killers," the source told Reuters news agency.
There was no figure available for the number of arrests on Sunday.
Eleven students were also injured in clashes in Morsi's home town, Zakazik, according to the website of the Al-Masry Al-Youm daily.
More than 2,000 activists, mostly from Morsi's Muslim Brotherhood, have been arrested in the past two months following the military's crackdown.
A Cairo court is due to rule on Monday on whether the Brotherhood should be dissolved, a verdict that could trigger more protests and violence.
Nearly 1,000 people have been killed since the army ousted Morsi after mass protests.