Mr. Nussbaum's Lesson Plan search (all grades all curriculum areas)
Challenger Center STEM Lessons
Smithsonian Curriculum Lesson Search
Engineering the Future: The Educator's Guide to Building and Constructing (STEM Lessons)
eGFI (Engineering) Lesson and Activity search
NASA STEM search
New York Times Learning Network
Printable Logic and Math Puzzles (Krazy Dad)
Printable Puzzles (many types) (Puzzle Baron)