Bobby's Girl

"Bobby's Girl" was a song in the early 1960s recorded by Susan Maughan. When Games class was called off on 29 March 1963 due to frozen pipes disabling the showers, the female fourth year students of Coal Hill School sang and danced to it in the assembly hall. (PROSE: Time and Relative)

Behind the scenes
It's actually very plausible that the song would be so popular at that time, and "Bobby's Girl" reached #3 on the just months before.