GeekDad writes: "This week I have chosen to review four applications, all from the same developer because for the last three weeks my children have played these games every night. They are engaging for primary aged children. These apps make math fun. They are improving my children's test results at school. And, the developer is not asking a ridiculous price for them. They are between $1.19 and $2.49, and based on that I'm pleased to share them with GeekDad readers."