Interestingly she was also said to be very close to her grandfather, George V, who thought for some time that she was likely to succeed to the throne, and was apparently also responsible for some of her constitutional teaching.
She was only nine when he died, so he wouldn't have had much of a hand in her more advanced education. Queen Mary, who was 'bookish', apparently took a hand in her education.
Elizabeth and Margaret, like most of their generation, would have had their education disrupted by the war - in their case, not able to travel to London for classes, lectures, museums, etc.