Charlie tells his reader about the senior prank at his school: they filled the pool with grape Kool-Aid.
All of Charlie's friends and his sister are talking about prom or college. Meanwhile, Charlie's a little upset thinking about Sam going to college.
Despite that, he's found time to finish The Fountainhead. Which, at over 700 pages, isn't an easy task.
He tells us about the philosophy in it—pretty straightforward—and how he's applied it to his own life: "Every person has to live for his or her own life and then make the choice to share it with other people" (4.8.11).
At the end of the letter, he tells us that his psychiatrist keeps asking him questions about his childhood, but he doesn't know why.