Mathigon is an excellent interactive website to explore maths. It has some fantastic resources. The ebook is amazing!!!!!!! The resources are all interactive, professionally presented and engaging.
One of these resources is Mathematical Origami over the weekend. It is a novel and unique way to look at 3D shapes, particularly for the secondary maths area.
There are three types of shapes (Platonic, Archimedian Solids, Stars and Solids). Each of these shapes comes with a description, a PDF document which outlines how to create the shape using origami and a NET of each shape. The site is interactive where each shape rotates when you click on it.
The Alice in Fractal Land is amazing. It is a slideshow which contains videos and maths problems to solve.
I highly recommend checking out this really cool site.