April 15, from 1 to 2:30 p.m. at Tower Hill Botanic Garden, 11 French Dr., Boylston, children ages 6 and up are invited to Build a Birdhouse. Assemble and decorate a “green” bird house, suitable for wrens, titmice and nuthatches. The bird house is made of specially laminated layers of recycled paper and will last one to two seasons before biodegrading. Learn all about the birds that might make your birdhouse a home and then go on a walk to our woodland birdfeeders to see the birds in action. Members: $15, Nonmembers: $18. Call 508-869-6111 or visit www.towerhillbg.org for more information.