Ahmed Benyermak fell from the seventh floor the day before he was to pick up his GCSE results. He had passed nine of them.
The 16-year-old was with friends playing on the 14th floor of the block in Paragon Road, Hackney, when they spotted a hooded and masked gang on bikes below and fled.
Witnesses said the gang also had knives.
Ahmed clambered on to an open balcony and began to climb down - but fell at the seventh or eighth floor. He was found at the foot of the block just before 4pm Wednesday by horrified passers-by.
Paramedics were at the scene within minutes, but could not save him.
He was described as a "good pupil" by the head of his school, Hackney Free and Parochial C of E.
James Roberts, 45, assistant site manager at Ahmed's school, said: "A gang of kids was chasing him - there were about five of them - and they were probably trying to stab him or something. He tried to climb down each balcony but then he fell.
Head teacher Richard Brown of Hackney Free and Parochial school said that Ahmed had never been in trouble.
He said: "I spoke to the family this morning. His parents were too upset to come and collect the results but I gave them to his brother and cousins.
"He was only here for a year and I know his family are really proud of the C grades he got in maths and science.
"I've spoken to teachers who told me he was a pleasant, quiet lad. He comes from a good family who are proud of his achievements. As a head teacher you get to know where the problems are and I didn't know Ahmed.
"He was a quiet lad who had his group of friends and was not someone you expected to be in trouble. He has just been a tragic victim."
Brown said the school will be keeping in close contact with the family and be helping them come to terms with their loss.
Police said they had found a number of abandoned cycles around the scene which were being forensically examined. They are also looking at CCTV.
A national soul searching is on even as police reveal teenagers as young as 13 are becoming involved in gangs and officers have started going into primary schools to speak about the dangers.
Mass searches are being conducted to recover knives.
Brainstorming sessions are regularly reported. Observers point to a range of causes, from poverty and isolation to lack of opportunity with education and employment. Preventative measures put in place included extra youth programmes and a hotline for parents.
Tottenham MP David Lammy said, "Without role models, young boys have to look elsewhere. An aggressive street culture replaces success in other spheres of life as an expression of masculinity.
"Young men become attached to gangs, which reinforce this subculture, rather than families who work against it."
Statistics show that 9 out of ten gang members are male and that 97 per cent of juvenile offenders are boys.
The minister for skills also blamed the "get rich or die trying" culture for undermining the value of hard work.
"Criminality has become a short cut to symbols of wealth and power that will otherwise take years of hard work to achieve.
"Young men need something purposeful to do, so that they learn to share, co-operate and produce, not just consume", he added.