Joel Smith, from Rugby in Warwickshire, died on Thursday evening, just a day after 100 students marched out of their school in protest.
The Police had to be called when the teenagers, from Bilton School, walked out when they were told they could only wear 'Team Joel' bracelets on non-uniform days. The bracelets were made to help raise money for the Teenage Cancer Trust.
Parents with children at the school have supported their children's protest, with one mother, Emma Howell, saying: 'I support my daughter. If she's excluded for five days there will be no punishment at home. She won't be missing out on anything because she's just revising anyway as she's in Year 11.'
Others have praised their children for standing up in what they believe in.
Bilton school has refused to comment further on the incident 'out of our deepest respect for Joel Smith's family.'
Friends took to Twitter to express their sadness at the teen's death, with one user writing: 'R.I.P. Joel. Lost his battle to cancer. Never to be forgotten, always in our hearts. My thoughts go out to his family friends.'
Facebook users also posted to his 'Team Joel' page, with one person writing: 'On behalf of the staff that remember you from oak field rest in peace Joel Lets hope these if a footie pitch up there for you to show your skills on. God bless you sleep tight beautiful boy xx.'