The international physics masterclasses allow high-school students to spend a day at a research institute and analyse real data from high-energy physics experiments. Conducted under the aegis of the International Particle Physics Outreach Group (IPPOG), the events are held in 24 countries with about 8000 students participating in nearly 120 nearby universities.

Lectures by particle physicists are followed by data analysis, and at the end of the day the students get to participate in an international videoconference to discuss their results.

In March 2011, for the first time, the physics enthusiasts performed analyses on LHC data, collected by three of the LHC experiments — ALICE, ATLAS and CMS.

We spoke to students and teachers, as well as members of the organisation team, who told us their motivation behind participating and what they gained from the Masterclasses of 2011.