Dynamite was a kid’s pop culture magazine published by Scholastic Inc. from 1974 through 1992. It featured articles about celebrities of TV, sports, and movies, and also included comics and puzzles and feature articles about just about anything that might interest a kid about 8-12 years old. It was a huge success, and a big part of the childhood of 1970s kids like me. Fun fact I never knew before: it was founded by Jenette Kahn when she was 28 years old; that same year, she became publisher of DC Comics and remained with the company until 2002.
Among the celebrities covered in Dynamite was Christopher Reeve, who made his first appearance on the cover of Dynamite #59, cover dated April, 1979. He shared the cover with Lynn-Holly Johnson, a professional ice skater turned actress who starred in the film Ice Castles, in this article about new stars. Here’s a copy of the cover and the article:
Many issues of Dynamite had pull out posters or special tip-ins like stickers or an uncut sheet of baseball cards. This issue had baseball cards and a poster of the cover photo from Ice Castles. Unfortunately, my copy of this issue had cards and poster removed, so all that is left is this center spread poster:
More information about Dynamite, including a list of cover appearances, can be found at this Wikipedia article.