Update (December 27, 2013): This site has been offline for quite a long time.
Manipula Math with Java is a Japanese website that has an excellent collection of Java applets that can be used for teaching and learning mathematics. There are 279 applet collections divided into the following categories: Middle School, Trigonometry, Vector, Calculus, Complex Numbers and Conics.
The site also contains Java Lessons for Creating Simple Java Applets.

279 Math Applets for Teaching and Learning: Manipula Math with Java is a Japanese website that has an excellent … http://t.co/LnevtVJO
Guillermo, see 3 fine applets at IES.jp above – 1. See under trig, the 6 trig function segments and values as a point moves around the circle at the angle shown; 2. Under complex numbers (a+bi)^(a+bi)^… they took a simple thing that I have in my book i^i^i, and made it 1000 times better, and got fractals; 3. the difference of 2 cubes, built originally by Maggie with the white Cuisenaire rods to get the identity (I think in the middle school set of applets). 4. They also did an applet: changing shapes with matrices, from my book of that name, on my website; and 5. there is also an applet on the Nautilus Shell and 6. A fine group of fine applets about Pythagoras, one of which makes a tree!
Don
Hi Don. I think you should call their attention.
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