Download here parts of A Cavendish Quantum Mechanics Primer.
This primer takes able readers from their penultimate school year to well into the second year quantum mechanics course in physics at Cambridge. It is not a textbook, but a primer introducing essential ideas, analytical skills and the solving of problems — much in the style of the Cambridge physics course.The Primer is challenging, but within the reach of a committed A-level student.See here for how it is used by A-level students, and how it can help you gain insight into Quantum Mechanics, and gain fluency and confidence in maths and physics.