This week's project appears to be an early 70s Columbia:
Apparently there were a bunch of 10-speed models named after different suburbs of Boston - Lexington, Lenox, Andover, etc. The model name was on the top tube, but the decal is gone on this one.
This looks to me like it was intended to be a U-08 knockoff. It has basically the same Simplex derailleur set as a contemporary U-08 I was working on a couple weeks ago, and the look is similar as long as you don't notice details like the crimped-in dropouts. There is a serial number list available online that pegs this as a 1965 frame, but I just don't think so. The rear derailleur has a fuzzy number that looks like a 71.
Basically a piece of junk, but a solid piece of junk with a history.