Everyone talks about the importance of getting young people interested in physics, but there can be no better way of doing this than to give school students a real project with a real deadline. So well done to David Cussans, a particle physicist at the University of Bristol in the UK, who encouraged a group of local school pupils to build an instrument than can detect cosmic rays – and then challenged the students to have their kit ready to fly aboard a hot-air balloon at this year's Bristol International Balloon Fiesta. The event marked the centenary of Victor Hess's discovery of cosmic rays, in a balloon, in 1912.

To find out if the students pulled off the challenge, Physics World went along to the fiesta with a film crew to record what happened as the balloons took off.