Algebradabra: algrabya.blogspot.com

Algeburble: algeburble.blogspot.com

MultipliXing: multiplixing.blogspot.com

Geometric Sparks: geometricsparks.blogspot.com

Geometric Jolts: geometricjolts.blogspot.com

SatisFraction: satisfry.blogspot.com

And some shorter blogs:

Triangle in a triangle: a proof

Angle at the centre (from Maths in School): Papers A and B