Here are some websites that can be integrated into an existing lesson or provide a fully prepared lesson for High School Math Teachers. If you are a teacher of ELA or Science, check out #3 below.
#1 -Free Online Resources from Courseware- Brought to us by the CEMC.
If you are a teacher of pre calculus or calculus, these are free online courses with videos, quizzes and exercises. Parts of the site are under construction. Each lesson is broken into modules. Thank you to my colleague, Anthony, for sharing this with me.
#2 -Transum.org offers math games, puzzles, resources and much more for Upper Secondary and High School students. There is an option to sign up for an account and create a class. Transum offers a large number of free games and puzzles. There is a lot to explore on this site.
#3 - Better Lesson offers thousands of K-12 rich Math, ELA and Science lessons from high performing Master Teachers.
Next Generation Science lessons
These lessons often include videos, group work, higher order thinking and integration of technology.
Check out this lesson on writing equations of parallel and perpendicular lines given the slopes and points.
The lesson is broken into 5 modules. Here is a peak at module 2.
Each module has an activity and additional resources on the side. These lessons are tried and true for use in the classroom.
There are many resources for High School Mathematics and I recommend checking out the above sites to supplement your lesson plans and instruction.