These books highlight the attributes of being a game collection as well as science book. Therefore, in addition to playing games, it can also be used as a science book that contains rich knowledge. Parents may to guide the child in reading the knowledge contents first, before getting on with playing the games. For children of younger age, mom and dad need not compel them to study the knowledge contents. children may simply play the games first, and then learn the knowledge when they get a little older. Children can also skip over the difficult game and come back to play it again later. there are 7 volumes in this series.