This guide is designed for educators planning trips to the National Aquarium in Baltimore. The first part provides tips on organizing a school visit and information on the aquarium lobby and exhibits. These exhibits are: (1) Maryland: Mountains to the Sea; (2) Surviving through Adaptation; (3) North Atlantic to the Pacific; (4) South American Rain Forest; (5) Atlantic Coral Reef; (6) Open Ocean; and (7) Marine Mammals. The second part consists of a chaperone's guide to the aquarium and 27 activities. The activities (which cover a wide range of topics and include, when applicable, suggestions for pre- and post-trip activities) are not divided by age or grade level since children's abilities vary. The last part includes the script for and titles of 56 slides which can be used to prepare a class for a trip to the aquarium, together with reasons why they should be used. An update of information about the exhibits is appended. (JN)