Here's some resources I think that a Science teacher, and a few for high-school teachers, shouldn't be without
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Crash Course YouTube Videos: https://www.youtube.com/user/crashcourse
This guy, John Green, is fantastic. I've used his videos to supplement my own lessons, either as introductory or summary pieces. He's also a great example to me of what teaching should be: fun, dynamic, and engaging
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Interactive Periodic Tables: http://www.ptable.com/ and http://elements.wlonk.com/ElementsTable.htm
I first came across these as a student teacher, and still use them today. Students can't/won't memorize abstract, non-applicable material. This shows how you can take traditionally 'boring' information, and relate it to things students can actually see, touch, and may have had experience with.
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Shakesperian Insult Generator: http://www.pangloss.com/seidel/Shaker/
Teenagers talk a lot of trash; why not introduce Shakespeare thru burns? Don't expect them to start using these around school, but it's a great way to convey Shakespear's intelligence and wit.
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People are Awesome: https://www.youtube.com/user/Hadoukentheband
I watch this, or something similar, almost daily. I also love to play these in the classroom as students are arriving. It gets you pumped and reminds you that the world, and life, is amazing.
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