CK12 - CK-12 Foundation provides a library of free online textbooks, videos, exercises, flashcards, and real world applications for over 5000 STEM concepts .
New Visions for Public Schools Living Environment Regents Prep Resources
Serendipity Studios Hands-on Activities for Teaching Biology to High School or Middle School Students
Serendipity Studios Minds-on Activities for Teaching Biology to High School or Middle School Students
PBS Learning Media / Science- Explore natural phenomena and scientific practices with videos, lesson plans, and interactive tools.
Britannica Science Launch Packs - combines up-to-date, curriculum-aligned content sets with tools that make it easier for teachers to differentiate instruction.
California Academy of Sciences - Flipside Science (Food, Water, and Energy)
BrainPop - Animated Educational Site for Kids - Science, Social Studies, English, Math, Arts & Music, Health, and Technology.