4/11 - Seining the Lagoon at the Gumbo Limbo Nature Center, 1801 N. Ocean Blvd., Boca Raton. Explore the grasses and flats of the Intracoastal Waterway behind Gumbo Limbo. Wear clothes that can get wet. No flip-flops or sandals. Old sneakers or watershoes only. Ages 10 to adult, children must be accompanied by an adult. Held again 4/25. 9:30-11 am. $7/members, $10/non-members. Reservations: 544-8615.