Short story, maybe 4-5 pages at most. This would have been in an issue of Boy's Life that was published by 1990 at least, probably a few years earlier as I read it in one of the magazines they kept in the computer room at my elementary school. Most of the details have been lost to me over the years, but it involved two boys who somehow wind up in a building on an alien planet. I'm honestly not certain if they wound up there by accident or if they were brought there, but they wind up hiding from the aliens by hiding in junk in the rooms. They eventually figure out the alien communications system, which I remember being described as being like a combination of a telephone dial and a typewriter keyboard, and either call in the cavalry (maybe the aliens were invading?) or at least find a way to get home.
In my head, they're Boy Scouts and the story is set in contemporaneous times, but that might have been the result of me conflating the magazine itself with the classic sci-fi they published (I know they ran some of the Norby stories, including a well-known comic adaptation).
From this thread, I found a list of stories in "The Boy's Life Book of Outer Space Stories"
The Man by Ray Bradbury
A New Game by A. M. Lightner
Tiger by the Tail by Gene Henderson
The Smallest Moon by Don Wilcox
Space Lane Cadet by William Hallstead III
Load of Trouble by Edward Wood
Best Friend by A. M. Lightner
The Terrible Intruders by James Hinrich
The Samaritan by Richard Harper
Quads from Vars by William Greer
I've done some quick Googling, and no dice on these ones, I suspect since they're from the 1950s and 1960s issues.