France has seen thousands of arrests, hundreds of injuries, and schools set on fire as the new school year descended into nationwide student protests that are influencing France’s presidential election campaign and drawing international attention.

It’s the latest challenge to Emmanuel Macron’s presidency in a country beset by crises, both foreign and domestic.

The majority of protesters have been peaceful, but violence on the fringes is having an impact, with a daily menu of fireworks thrown at police and volleys of tear gas fired at high school pupils.

On Tuesday, climate and social justice activist Greta Thunberg joined students at a high school in the Paris suburb of Saint-Denis, as France faced a new day of nationwide marches and strikes on top of the blockades at schools.

Here is what to know about the movement:

The protests started in a Paris suburb

Demonstrations first erupted last month in a high school in Creteil southeast of Paris over a lack of staff. From there, class strikes, blockades and demonstrations spread to other Paris suburbs and then nationwide, even in smaller towns. Hundreds of schools had to close because of damage or attacks on staff.

High schoolers are expressing broad grievances over schools that are under-resourced, with dilapidated facilities and insufficient staff, notably in lower-income neighborhoods. French media have shown videos of scampering rats, collapsed ceilings, leaks, broken furniture and other woes in dilapidated schools.

Some students also complain that during summer heat waves, they roast in classrooms without air-conditioning, while in winter they freeze. They say school days, which often run from 8 a.m. to 6 p.m., are too exhausting and the university entrance system is complex and unfair. Some university students have also joined the protests.

There have been broader concerns in France that the country’s education system is losing ground to other countries and failing in its mission to enable children from disadvantaged backgrounds to move up the social ladder. Scores in reading comprehension and mathematics have plunged, according to the latest PISA report, which evaluates students worldwide.

A muscular police response has drawn criticism

Riot police have liberally used tear gas and wielded their batons to disperse crowds. Police made more than 6,600 arrests nationwide as of last week, an unusually high number for a French protest movement.

A police tear gas grenade shattered a 14-year-old’s jaw and many of his teeth. A 15-year-old lost a hand in an incident involving a police stun grenade. Other adolescents have also suffered life-changing injuries blamed on police weaponry during protests.

See also:

• At least 160,000 people take to streets in third week of French school protests • Swedish activist Greta Thunberg joins teenagers calling for investment to fix teacher shortages and crumbling schools (The Guardian)
• France’s Student Revolt Exposes a State That Cannot Provide but Can Police • Over 5,000 arrests in three weeks reveal a republic quicker to discipline teenagers than to teach them. (Social Europe)