What it teaches
Taking a fraction of a quantity: half of 10, a quarter of 12, three quarters of 8. This is what fractions are for, and it is much easier to grasp than the abstract idea of a number between nought and one.
It also builds the link to division, which is the thing that makes fractions manageable later. A quarter of twelve is twelve divided by four, and a child who sees that once rarely forgets it.
How it works
A fraction and a number appear. The picture comes with the question, not after it — twelve counters in four groups — because the picture is the explanation rather than the rescue.
On a wrong answer the groups are separated on the screen so the child can count the one they need.
What to look for
Fractions belong to klasa IV, so this is here for a child who is ahead rather than as part of the first levels. A seven-year-old who can halve and quarter confidently is ready for it; one who cannot divide is not.
The common confusion is between the two numbers in the fraction. If three quarters keeps coming back as three, the child is reading the top number as the answer.