Plot

A young boy with stunted growth is convinced that God has a great purpose for him.

Simon Birch tells the story of Joe and Simon's heart-warming journey of friendship. Simon Birch was born with a condition that makes him much smaller than all the other kids in town. Now, due to his condition, Simon thinks God made him this way for a reason and highly believes in God. Together, Joe and Simon go on a journey of trust and friendship to find the answers to many things. Their friendship is put to the test when some unfortunate events happen.—Thorpe89

Simon Birch believes that God made him for a special, heroic purpose. Simon and his best friend Joe Wenteworth are both outcasts in their tiny New England town: Joe is the illegitimate son of the town beauty, and Simon, at age 12, is so small that he still plays the infant Jesus in the church Christmas pageant. In the summer of 1964, friendship is put to the test when Little Leaguer Simon hits a foul ball that strikes and kills Joe's mother. Together, they try to find out who Joe's father is. Just as they succeed, the time comes for Simon to fulfill the destiny he believes in. A situation arises that demands a hero - a very small hero.—Anthony Bruce Gilpin

A middle aged man named Joe Wentworth stands in a graveyard, visiting the grave of his childhood friend Simon Birch, who died in 1964 at the age of 12. He begins to narrate the story of their last few months together.

Simon had been born with a genetic disorder that made him by far the smallest baby ever born in their town, and it appeared he was going to be a dwarf; by the time he was 12, he was barely half the height of his classmates. This made him a frequent object of ridicule by the other children, but it helped him bond with Joe, because Joe was also looked down upon in town, although for different reasons. Joe was an illegitimate child, and his mother Rebecca had never revealed the identity of Joe's father to anyone, promising to tell Joe only when the time was right.

Simon's parents were sour and callous, and didn't seem to care at all about Simon's well being, so Simon spent a lot of time at Joe's house, where he lived with his mother and grandmother and her maid. Simon went to church and Sunday school with Joe, although his own parents didn't go to church. Simon is convinced that God made him a dwarf for a reason, and he has a destiny to fulfill, but he does not know what that entails. Simon also loved to play baseball, although he got little playing time, and when he came to bat, his coach told him not to swing. Like the dwarf major league player Eddie Gaedel, Simon was so short that the opposing pitchers inevitably walked him on four pitches because they couldn't master his tiny strike zone.

One day Rebecca meets Ben, a drama teacher, and invites him over for dinner. Ben gives Joe a model armadillo as a present. Simon likes Ben immediately, but Joe remains aloof, for he knows Ben is just trying to ingratiate himself and he wants to learn who his real father is. Ben and Rebecca begin dating, to the point where one day Ben joins the family at church. While there, Simon embarrasses Reverend Russell with his unfiltered observations about church. The Sunday school teacher, Miss Leavey, berates Simon, telling him that he and his family are freaks and don't belong. Only Rebecca stands up for him.

On October 30, the local baseball team is losing badly. The coach sends Simon up to bat and tells him to swing, hoping that he will strike out and get the game over with. Simon hits a foul ball that hits Rebecca on the head, killing her instantly. Simon gives his baseball cards to Joe to apologize, and Joe gives him the armadillo. Eventually, on Ben's advice, he also returns the baseball cards, since he knows they were Simon's favorite things. Simon observes that the baseball turned up missing after the accident, and speculates that Joe's father may have been there and taken it, as something by which to remember Rebecca. Joe's grandmother informs him that she feels her own time is short and Joe will become an orphan if she dies, and have to fend for himself. Even she has no idea who Joe's father is, as Rebecca had never told anyone, even in confidence. Joe becomes more resolved to find out who his father is.

Simon and Joe form a theory that maybe the gym teacher, Mr. Baker, is Joe's father. To test the theory, they break into his office at school one afternoon, to look for the baseball. Joe finds a baseball, but it is clearly not the same one. Joe is bitterly disappointed and trashes the office in a fit of anger. Both of them are caught and taken to the police station. The police chief tells them that to avoid going to jail, they must go with Reverend Russell on the church's Christmas weekend trip for the younger kids to help out. The boys reluctantly accept this suggestion. Ben picks them up and takes them home, and Simon talks about his beliefs to him. Ben promises Joe that if he ever learns who Joe's father is, he will tell Joe.

The church's Christmas pageant arrives. Miss Leavey organizes it, assigning roles to the children. Simon will be the Baby Jesus, a girl named Marjorie will be the Virgin Mary, and an overweight boy named Howard with a fear of heights will be an angel. Others are selected to play Joseph, the Wise Men, and shepherds, the most coveted role because they don't do or say anything. Miss Leavey quickly becomes stressed out by all the unruly children. Simon offends her again with his unfiltered observations, and Reverend Russell confiscates his baseball cards until after the pageant is over. The pageant turns out badly. The children forget their lines, Simon is unable to restrain himself and grabs Marjorie's boobs, and one of the ropes holding Howard breaks, leaving him swinging through the air, where he vomits on Miss Leavey. Reverend Russell blames Simon alone for the disaster, bans him from the weekend trip and refuses the return of his baseball cards. Outside the church, Joe tries to comfort Simon. Simon starts coughing, his health has always been shaky and now he is apparently catching a cold.

While Reverend Russell, Joe, and the younger children go on the trip on a bus, Simon breaks into Russell's office to retrieve his baseball cards. While there, he also finds the missing baseball, implicating Russell as Joe's father. He rushes to tell Ben what he found, and Ben makes good on his promise by driving with Simon to where Russell and his group are, so that he can tell Joe. When they get there, they find that Russell has just told Joe himself. It is now clear why Rebecca had never told anyone, for the scandal would have been a lot worse. Joe begins to wish he hadn't learned this.

Simon joins the other children on the way home, and Ben follows alone in his car. The bus has an accident on the way, running off the road, down a steep hill, and into a freezing cold lake. Russell is knocked unconscious, and the bus driver panics and flees, leaving only Simon to take charge of the younger kids. With larger Joe's help, he gets all of them safely to shore. The bus sinks in a few minutes, and Simon almost drowns getting the last younger child and himself out of the bus. Ben and two bystanders come down the hill to help, and they revive Reverend Russell.

Everyone is taken to the hospital, where Joe grudgingly acknowledges Russell as his biological father. Most of the people make a full recovery, but the dunking in icy water has turned Simon's cold into something much more serious. Simon wakes up long enough to tell Joe that he now understands what God's plan for him. His small size was essential in rescuing the other children, especially the last one, from the sinking bus. He and Joe say goodbye, and Simon dies.

The adult Joe narrates that his grandmother and the maid both died the following summer, and Ben legally adopts Joe as his son just before his 13th birthday. Back in the present day, Joe's teen-aged son, also named Simon, comes to remind Joe that he has a soccer game to go to, and they drive away.