A stunning animated slideshow which explores sequences, fractals, Fibonacci sequence, the golden ratio, Pascal's Triangle, and more. The text at the bottom explains each concept very clearly. The maths of Nature, of the real world, is emphasised. The text says 'It seems that the Land of Mathematics is even more curious and mysterious than Wonderland. Only that it is real...'
A dynamic image which shows the creation of a parabola as the locus of a point equidistant from the focus and directrix. A gif file.
A gif file that shows how an ellipse is created using 2 foci
A YouTube playlist demonstrating the construction of four special quadrilaterals from paper rectangles.
Rhombus, trapezium (trapezoid), parallelogram, kite.
(Click through for the playlist.)