K nex 77075 129 piece investigating solar energy set for 2 to 3 students k nex 77075 the k nex 77075 investigating solar energy set allows students to harness the energy of the sun and convert it into electricity to power their models p p the set makes 3 solar powered models one at a time and contains 129 parts sufficient for 2 to 3 students working in small groups p k nex 77075 investigating solar energy