You know the saying: Recyle, Reduce, Reuse. Now learn the skills to do it. In conjunction with the Mass Audubon at the Boston Nature Center, kids can dig up compost and discover just which critters are helping to break it down. There will also be a scavenger hunt and craft session along with lessons about reducing water and electricity.
2 p.m. - 3 p.m., $7 for nonmembers, $5 for members, Boston Nature Center, 500 Walk Hill St., Mattapan, 617-983-8500, www.massaudubon.org