State Senator Jamie Eldridge and Dean Cavaretta are going head to head in a race for public office for the first time, but the two state Senate candidates are no strangers: They went to high school together.

The two Acton residents both attended Acton-Boxborough Regional High  in the late 1980s, with Cavaretta graduating in 1989 and Eldridge two years later. Cavaretta, a Republican, and Eldridge, a Democrat, said they didn’t know each other well in school.