Hippocampus offers educators a wide variety of multimedia content online, including videos, animations, and simulations. An additional feature offers educators the ability to create "playlists" for their students, which correlate specifically to their particular instruction material.
Founded in 2002 by Nobel Laureate Carl Wieman, the PhET Interactive Simulations project at the University of Colorado Boulder creates free interactive math and science simulations. PhET sims are based on extensive education research and engage students through an intuitive, game-like environment where students learn through exploration and discovery.
All the materials in MERLOT are reviewed for suitability for retention in the collection. Many undergo the more extensive "peer review" for which MERLOT is famous. MERLOT presents annual awards for various categories of materials added to or used in the collection. As described in Material Link Checking and Removal, all material URL's in the collection are reviewed frequently for sustainability.
The LibreTexts approach is highly collaborative where an Open Access textbook environment is under constant revision by students, faculty, and outside experts to supplant conventional paper-based books.