Resumes well the concepts being covered in class, just briefly. And provides exercises related to check understanding. I use it to take over the points that my daughter did not understand. It calls itself the way! I also took one on the problems that is an excellent complement very friendly for children. In all, there is a summary that allows to directly find the desired item (eg, time or mass measurements etc ...). Doing the exercises of a page, so covering a concept, takes about 10 to 15 minutes.
