Join Park Rangers and site staff in building your own bluebird box to welcome spring at your home. Pre-registration is required by Friday, march 10th. Participants should meet at the Main Pavilion. Workshop will be postponed to March 25th in the event of inclement weather. Ages 8 & up, adults with or without children welcome, children must be accompanied by an adult. Materials fee: $5/box. Call 610-666-5371 for more information.