The subtraction tests have 9 standard levels and 2 master levels. You will also find a speed test level included which if you are good enough will put you on the leader-board. The tests start at a very basic level which is good enough for children just starting out. As you work through the levels the questions get harder.
The first 9 levels on the subtraction tests give you a choice of sitting a 20 or 40 question test. You simply need to tick the checkbox next to the level you want a 40 question test on. Then click the level and the test page will be shown.
The standard subtraction test screen looks like the image below. As you can see the test screen keeps score of how you are doing. Remember if you get 5 wrong the test will end and restart. The idea of that is so you are confident of knowing enough on that level before being moved up to the next level. If you moved up the levels to quick the questions would be to hard. As you can see from the image below if you get one wrong you will see a sad face. The idea of this software in general is that all children get to practice as much as they want at home. Im sure we all want the same thing for our children and that is for them to be a natural maths whizz.