The Royal Institution (Ri) offers STEM Masterclass projects for sixth-form students. Schools taking up this opportunity bring an exciting volunteering project to their STEM sixth-formers, who undertake Ri training and small-group work to develop workshop activities. The project culminates with the sixth-form students delivering fun STEM Masterclasses to a young audience via Ri primary Masterclasses run at their school. The three big wins of Masterclasses are: a win for primary students taking part in the inspiring workshops; a win for sixth-formers who gain invaluable life and subject skills as they develop and lead the workshops; and a win for secondary schools seeking ways to connect with local primary schools.