Teaching

This is an amazing resource:   a collection of science demonstrations from Harvard Natural Sciences Lecture Demonstration Services.

https://sciencedemonstrations.fas.harvard.edu/catalog

There are hundreds of demonstrations in the archive.  Each entry includes an in-depth description of the scientific principle(s) on display in the demonstration, as well as detailed instructions on how to execute the demo.

Topics include Newtonian Mechanics, Light and Optics, and Thermal Physics.  There is also a collection of mathematical demonstrations, as well as a small set of videos.

And be sure to check out their Facebook page here:  http://www.facebook.com/NatSciDemos

This is a collection of free online college courses from the Indian Institute of Technology — Delhi.

http://nptel.iitm.ac.in/courses.php

There are a wide range science and technology courses represented here:  Electronics, Mechanics, Information Systems, as well as several Mathematics courses.

There is a mixed-bag of resources available here:  many of the Basic Courses have a full curriculum of lecture videos, while some of the more advanced courses currently offer only on-line syllabi.

Another nice resource for students and teachers!

This is the website for the National Association of Math Circles:

http://www.mathcircles.org/

A Math Circle can be many things, but essentially it is a group of people who get together to have fun with mathematics.  Math Circles exist for young children, older students, teachers, and professionals, and some groups involve all of the above!

There are Math Circles all over the world, and this website aims to create a directory of such circles and provide resources for students and teachers alike.  Use this resource to find a Math Circle in your area; or, start one of your own!