Riccardo Orlando
  • Member for 5 years, 8 months
  • Last seen more than 1 year ago
  • Dalmine, BG, Italia
Free, open-source, customizable, interactive math books with gaming elements
2 votes

I don't think it has been listed yet, so here is my suggestion: Khan Academy. I used it to great effect to refresh and even come to master the basics, and it includes every maths topic taught in ...

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