Thousands of Italian school students are protesting nationwide over work placements which they say contribute little to their future job prospects.
The students are calling it a "strike" in 70 cities. Student unions organised the protest via social media, reports BBC.
Italy's Student Network says "no more exploitation through free labour".
It says 95 per cent of schools - about 900,000 children - participate in work experience schemes. Italy has the EU's third-highest jobless rate, at 11.2 per cent.
There was some vandalism by protesters in Milan, targeting what they saw as symbols of capitalist exploitation: the chamber of commerce building, a McDonald's restaurant and a Zara clothing store.
The student unions claimed 200,000 youths protested across Italy - however, there was no independent estimate of the total.
The students want the government to fulfil its promise to draft a statute defining the status of people doing work experience and a code of ethics for companies using them.
The strike - with rallies in Rome, Naples, Milan, Salerno and other cities - was also in protest against alleged underfunding of state schools.
"We want work placements that provide real alternative training and quality for all," said Student Network national co-ordinator Giammarco Manfreda.
Italy "continues to lack rules defining who can or cannot offer work experience", he added.
"We're tired of being humiliated by our companies, whose work experience does not amount to training at all."
An "anti-exploitation" statement from the student unions said "we are students, not merchandise in the hands of businesses" and "we are sick of being sent to wait on tables".
Italian Education Minister Valeria Fedeli defended the centre-left government's education policy. She said internships gave students "complementary skills that enable them to face the future with more knowledge".
But she pledged to address the students' complaints and work to raise the quality of internships, Ansa news agency reported.
Italian media reported that paint was daubed on some buildings in Milan and a McDonald's restaurant was pelted with eggs and tomatoes.
Youths also smashed a window at the Milan offices of the centre-left Democratic Party (PD), then hurled paint and smoke bombs into it.
Internships for students at some global businesses, including McDonald's and Zara, were launched by the PD government of former Prime Minister Matteo Renzi in July 2015.
Youths in the last three years of school have been getting the work experience, branded as "exploitation" by the protesters on Friday.
In a statement (in Italian), McDonald's said its outlets across Italy were taking "up to 10,000 students each year", with the aim of helping young people develop skills required in their future employment.