Donsantos Fracciones is an educational tool, totally in Spanish, that will help students in Primary education to revise everything related to fractions. It includes a multitude of examples and exercises from basic to more advanced levels.
From Donsantos Fracciones you can do proper fractions, improper fractions, convert improper fractions to mixed (and vice versa), represent fractions, equivalent fractions, comparisons between different fractions, ordenation, amplification, adding, subtracting, multiplication, division, reduction to a common denominator, etc.
This way, Donsantos Fracciones is a fundamental support, in the branch of mathematics, to what is learnt at school.