It's a Charmed Life

Harry Potter/Charmed crossover. Triplets Namine, Kairi and Rayne get a letter from Hogwarts telling them they are witches. Whilst at Hogwarts Rayne finds the book of shadows and finds out they are what are known as the Charmed ones and unleashes their additional powers. Namine can move things with her mind, Kairi can freeze things and Rayne has premonitions.