Go green (and easy on your wallet) this Halloween. In honor of National Costume Swap Day, Kids Discovery Museum will host its third annual Costume Swap through Oct. 30.

Bring any gently used complete Halloween children’s costumes, costume pieces or accessories to KiDiMu and exchange them for something new (or “new-to-you”). Pick-up or drop-off only also available.

The program is free with admission or membership.