Preferably online, and preferably starting from really basic stuff. Like, multiplication table kind of basic, and with as idiot-proof explanations as possible. Would anyone have anything to recommend?
Khan Academy has lots of great videos starting from basics. Also maybe BBC Bitesize, though I don't know if there are location restrictions on that. You'll probably want to check the stuff under KS2 (under "Primary") for foundation things and the KS3 and GCSE categories (under "Secondary") for the rest. Assuming you're not familiar with UK education systems, which you may well be. ETA: Oh wait, you said "maths". You probably are familiar with Key Stages, then. ETA2: Actually it looks like Bitesize has changed significantly since I last used it. More of a teaching resource, less of a self-study one. Probably not that useful to you.
Seconding the recommendation for Khan Academy. I don't know about it as far down as the multiplication tables go, but I've done some of its basic algebra stuff and it's overall been better than expected.
