We haven't, but I'd be interested to hear a report if you do try it or if anyone else has. FWIW, have just signed DS6 up for Alcumus (Art of Problem Solving's new, currently free, online programme for counting, probability and algebra), which we like so far. I'm just a little bit wary of the Carnegie website's emphasis on maths for all, etc., suggesting that it might be comparatively slow paced.

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