Check out these Math Links:

Desmos Graphing Calculator (also available as an app)

Wolfram Alpha (calculates anything!)

Graphic Lines (for understanding slope and intercept)

Geogebra (construct geometry diagrams and much more)

Virtual Manipulates for Junior Math

Cut the Knot – Interactive Math Activities

Gizmos Math Interactive Simulations

Phet Simulations


Check out these Science Links:

The Physics Classroom (Interactive Physics Simulations)

The National Science Digital Library