How do I learn maths?

I forgot maths. I did maths for my GCSEs and A-levels, but I did bad and I want to learn maths.

Is there any book that will teach me maths? I keep coming across books by K.A. Stroud. Are they good? Should I get those?

Keep in mind this is British maths, not American math, so if there are any differences, I would prefer the British version.

read paperts mindstorms http://www.amazon.com/Mindstorms-Children-Computers-Powerful-Ideas/dp/0465046746

this is how math should be taught. Learning math through a computer is like going to france to learn to french. Computers bring math to life. Read the texts and implement the algorithms. You can use mathematica, canvas/javascript, opengl or whatever you want.