Teaching Year 8 pupils equation solving through balancing today; for me an important skill particularly for an average attaining group that will be going through the higher GCSE paper in the future. I am using my cups and counters tomorrow for a presentation to a CPD conference so decided not to use them today and so used an alternative I haven't used in a long time - Balancing Equations for the National Library of Virtual Manipulatives from Utah State University.
I really like these applets, and if you can navigate through the American grade system (UK teachers anyway, US teachers wouldn't have the problem!) you can find some real gems here.Some of my favourites are:
1) Multiplication of Fractions - A great applet showing fraction multiplication using overlapping shading of rectangles.
2) Sieve of Eratosthenes - Set how big you want a grid and then click numbers to remove multiples of that number.
3) Algebra Balance Scales - Great for physically showing what happens when solving equations through balancing; is a bit limited because of size of the scales and the need for whole number solutions but choosing careful equations can illustrate the point.
4) Function Transformations - Shows the effect of changing constants in the equations of well know graphs.
5) Stick or Switch - Great little applet for the Monty Hall Problem.
6) How High - Great volume of cuboids problems: how high will the liquid be in one container when it is poured in from another container?
7) Tessellations - Allows pupils to experiment with single shapes to find regular tessellations and different combinations of shapes to find semi-regular tessellations.
8) Spinners - Use different spinners to produce data for probability investigations or questions.
All of these are simple interactives that pupils can use at the board or in computer rooms to explore or demonstrate these ideas. Well worth a look.