Children ages 8 through 12 explore a desert oasis, from the source of the water to its properties, its quality and the plants and animals that depend on it, from 8 a.m. to 4 p.m., Tuesday through Friday, June 12 through 15; $60. A field trip to Mount Lemmon is included; the group will study life in a mountain stream. Registration is required. Call 615-7855, or email [email protected] to register or for more information.