This $9-million facility is the ne plus ultra of interactive fun for kids. Highlights include a climbable eagle's nest – a slide tumbles down from here to the Puget Sound interpretative area, where there's an underwater world and a crane-lift port. Open until 9pm on the first Friday of each month.
The WET (Water Education & Technology) Science Center next door (open 10am to 4pm Monday to Saturday) is dedicated to water-reclamation education (and has an artificial creek to play in). Admission is free.