An American Summer (1991)

In this youthful drama, Tom, a 14- year-old who's parents have just divorced, is abruptly uprooted from his wealthy Chicago home and sent to the strange land of LA to live in the far-out beach bungalow of his aunt, an aging hippie still stuck in a by-gone era. He is unhappy with the new arrangement and finds his new bohemian lifestyle strange and the activities of his new peers, stupid. His life begins to change a bit when he befriends a young surfer named Fin. At first he thinks of the fun-loving Fin as a real dolt, but later he admits he was wrong. Like the Tom Sawyer and Huck Finn characters on which they are loosely based, the two new friends soon find themselves having a series of adventures, some of them dangerous; by the summer's end, Tom finds himself wiser, accustomed to California, and a lot more grown up.

Unfortunately the movie An American Summer is not yet available on HBO Max.