In order to establish the close bond between Smalls and Benny, the director had Tom Guiry and Mike Vitar meet and rehearse together weeks before the rest of the kids showed up to film. It worked so well that the other kids genuinely believed the two actors had been friends for a long time.
Mr. Mertle (James Earl Jones) shows the boys a photo of himself with Babe Ruth and Lou Gehrig. Of course it is a retouched photo. Jones' head was put on the body of Hall Of Fame slugger Jimmie Foxx who was the real player pictured with Ruth and Gehrig. The real photo can be seen in many baseball books.
The vomit used in the ride scene was made from split pea soup, baked beans, oatmeal, a little water and some movie gel. They used paint guns to discharge it and they actually nailed a few people in real life by accident. The chewing tobacco was made from beef jerky and licorice.
Contrary to what was previously stated about Babe Ruth not playing with black baseball players due to Jackie Robinson not breaking baseball's color line until 1947, what the film does not explain is that major leaguers used to barnstorm in the off-season with players from the Negro Leagues. According to John Holway, a Negro League historian, "Ruth played against Negro Leaguers in Cuba, all over New Jersey and out West in Kansas City and St. Louis." (NYTimes)
When the narrator is describing how everyone grew up towards the end, he says that Bertram (Grant Gelt) "got really into the sixties, and no one ever heard from him again". In real life, Gelt would go on to land a part in The '60s (1999).
The Vincent Drug store that is seen when Smalls first goes to the "Sandlot" was also used five years earlier in Halloween 4: The Return of Michael Myers (1988) when Rachel and her friend take Jamie to pick out a costume. It was also used the next year in Halloween 5 (1989): The Revenge of Michael Myers in the scene where the Man in Black steps off a bus and makes his way through town.
Ham Porter's famous line, "You're killing me, Smalls," is a paraphrase of the famous quote, "They're killing me out there, Whitey," spoken by Denver Broncos coach Lou Saban. The line was also paraphrased the previous year in another baseball-themed film, A League of Their Own (1992).
When the boys are in the pool watching Wendy Peffercorn, the dialog: "She don't know what she's doing" and the answer "Yes she does, she knows exactly what she's doing" is the same as in a similar scene in Cool Hand Luke (1967).
The name of the other park the sandlot kids play the little league team at was the L.C. Romney Baseball Park (on the scoreboard at 47:40 and 48:04). L. C. Romney was a commissioner of Salt Lake City and a democratic candidate for Governor of Utah in 1956. The film was shot in Utah.
Both James Earl Jones (Mr. Mertle) and Karen Allen (Mom) have starred in popular franchises that were produced by George Lucas. Jones in Star Wars: Episodes lll-Vll and Allen in two of the Indiana Jones films Raiders of the Lost Ark (1981) and The Kingdom of the Crystal Skull (2008).
In the scene where the boys are beating up Smalls over not knowing who the Great Bambino is, Squints can be seen spitting,then accidentally poking himself in the eye with his glasses, then spitting again.