I've previously posted an
index of all the SPACE CONQUERORS! comic strips that appeared in BOYS' LIFE magazine from 1952-1972, now archived online in Google Books.
There was also a series of short stories in BOYS' LIFE from 1959-1989 about a Boy Scout patrol that found an abandoned time machine, then learned to use it to explore time and space. The stories were by "Donald Keith", a pseudonym for the father-son team of Donald and Keith Monroe.
I'm in the process of making a detailed synopsis of these stories, but
beamjockey has created an index
here (Also in
Wikipedia).
The first story was in
December 1959, the last story was in
September 1989.
But, since it's Christmas Eve, here's the December 1973 story
"Santa Claus and the Time Machine", courtesy of Google Books.