Chapter IV: I Broaden My Mind.
At the age of thirteen, Lewis went to a prep school where he began to be educated. The first year he had a great teacher and matron and it was a good time. But, it was during this time that he lost any semblance of Christianity that he had. It was partly because of the matron who was dabbling in all sorts of spiritualism. And, perhaps more importantly, partly because he had set unobtainable standards for his own version of Christianity. Nobody had told him that "we must never in prayer strive to ext or by mastery what God does not give." As a result, it was relief to cast off his religion.
After a year both the proctor and the matron changed. The new proctor was freshly out of college and taught Lewis the ways of the world. He became interested in how he dressed, music, theater, etc. and not necessarily in a good way. In addition, his sexuality was realized and he became a bit of a pagan. Interestingly enough, he felt no guilt about his actions at the time.
Chapter V: Renaissance
Lewis paints a dark picture of boyhood that he must have experience. It lacks imagination and joy and is full of the pettiness of boys and their peculiar traits. He vividly remembers his return to joyful experiences. It is an odd story and has to do with a picture and his immersion into Wagner's world of the Ring. But, it changed his focus a bit and he became immersed in imaginary worlds. He describes the world he and his brother created called Boxen in some detail. But, interestingly, he never had any illusion that these imaginary worlds were real.