This document lists and briefly describes various activity aids that can be used for teaching, including experimentation, field trips, demonstrations, dramatics, programmed instructions, teaching machines, computer-assisted instructions, exhibitions, dramatizations, science kits, nature calendars, computer CDs, interactive CD-ROMs, PowerPoint presentations, museums, planetariums, aquariums, terrariums, vivaria, farmers conferences, farmers meetings, TV talks, and seminars. Some of the aids, such as teaching machines, computer-assisted instructions, interactive CD-ROMs, and terrariums, include short definitions or descriptions.