On Tuesday 15 March 2016, Maynooth University will join the International Masterclasses in particle physics for the fifth year running. These Masterclasses give secondary school students the opportunity to discover the world of quarks and leptons for themselves, by performing measurements on real data from CERN, meeting active particle physics researchers and linking up with like-minded students from other countries. We will join thousands of other secondary school students at more than 100 universities and laboratories around Europe and worldwide in a programme stretching over four weeks. There will also be Masterclasses events at TCD Monday 29 February and at UCD Monday 14 March. Physics at the most fundamental level - the smallest and most basic building blocks of matter - is an exotic world. But a few introductory talks and working with data from CERN will give the students insight into the fundamental particles of matter and the forces between them, as well as what went on during the Big Bang. In the morning, the students will be introduced to particle physics, experiments and detectors in lectures given by active particle physics researchers. After having lunch with lecturers and tutors, they work on their own with data from the ALICE collider at CERN. Afterwards they will participate in a video conference with students from Copenhagen, Nantes, Padova and Bari and moderators at CERN, where they will discuss and compare their results.