Arts Collaborative Medford is hosting a pop-up shop featuring the work of Medford maker Caoin Springer, one of 30 artists who live or work in Medford whose art is sold through the ACM Gift Shop. Pick up a puzzle, mix it up with some paper doll making, and check out ACM’s two current exhibits — “Room To Breathe” and “Imprint in Print”— on the last weekend before these shows close.