OK, so as an American you don't know anything about Cricket. That's OK. What you need to know, the film gives you because it really isn't about the game, it's about families, friendship, and racism. Set in the 1960s London, but not tied to a specific year, we get to know David Wiseman (played invitingly by Sam Smith) as a boy full of daydreams, a tremendous love for Cricket, and absolutely no ability. He can't catch, can't throw, can't run, and can't hit. Of course, this means that his friends at the school he attends (we would call it a private school in America) make fun of him. David doesn't care because he loves the game so much he is oblivious to the state of his skills. The coaches finally put him on the team to change the scoreboard (there are lots of runs in Cricket).
He lives in a working class neighborhood with its tiny yard, and the row houses mean that the neighbors are all busybodies, too. Being the only Jewish family in the neighborhood they get treated differently, but coldly polite since it is fewer than 20 years since the end of the World War II and the holocaust. David's father has a little shop that consumes all of his time and attention. In one scene, the family is sitting around the table making cushions to sell in the shop.
David's mother, Ruth (Emily Woof), is clearly younger than the father and seems almost too pretty to be the wife of a small time shopkeeper. This becomes an important fact in the story. She is a person of dreams and emotions. And while she is devoted to her family and especially her children, the father's obsession with work denies her the emotional fulfillment she clearly needs.
A new family is moving in next door to them and somehow the neighborhood makes it the Wiseman's responsibility as to who moves in. Why, I cannot fathom. People are crushed when it is a Jamaican (read black) family. Delroy Lindo plays Dennis with real presence and emotional complexity. A very friendly man, Dennis has clearly been away from his wife and daughters for a long time. He begins setting up a practice Cricket net in their small backyard and David is in rapture. He befriends Dennis and his daughter, Lilian, whom Dennis is teaching to play the game. Dennis has great skill at the game and is devoted to it and apparently played it quite seriously.
The rest of the movie exposes the elements set out here. David becomes great friends with Judith, but the issue of race is still, sadly, in their friendship. Dennis gladly teaches David how to play the game and Ruth is grateful to him. However, the friendship she develops with the more emotionally present man next door leads to a couple of acutely uncomfortable scenes (for those who think the marriage relationship to be sacred) that reveal other important aspects about Dennis and his devotion to his wife and daughters.
The neighborhood racists exacerbate the normal tensions that exist when people suppose that race matters in the least (as almost everyone did in the 1960s). Difficult drifts to worse and a crisis occurs that wakes everyone up to the destructive nature of their bigotry.
I found this to be an enjoyable movie. It can be a good film to discuss with your children, but those two scenes between Ruth and Dennis will require some thought on how to use it with your family and probably makes the film unusable for young children. However, they might not even catch what is happening between them.
It is well acted, has a pretty good story, and as I noted, the fact that you are unlikely to know Cricket here in the U.S. is not important. It only uses Cricket as a means to tell the story, it isn't really about the game.