Elementary schools in Wellesley have unique artistic signatures, from the new mosaic display within Sprague Elementary to the red/white/blue handprints at Bates to the Fenway mural at Upham.

But the most unusual of all are the “chalk” outlines on the back brick wall at Hardy School. Naturally, we’ve taken a few family pictures against the backdrop, figuring the outline brothers would get wiped away at some point, victims of a campaign against this possibly disturbing art. Then again, it’s a pretty common school assignment in town for kids to trace each other.

Alissa Gillis, an art specialist at Hardy, says the outlines, made with paint, are a good source of jokes but are a bit of a mystery. A school custodian says the ghostly outlines have been there for at least 25 years in an area that was once a playground but is now used for staff parking.

Lingering questions: Who were the models for these outlines? (the one on the left has a mighty bulging bicep) When exactly did they go up? Why?

Coincidentally, as we were writing this we happened upon a couple more chalk outlines, these in Harvard Square at the Harvard Lampoon building on Bow Street.