If you want your child to do well in school, its best to start with them at a young age teaching them about concepts that they would later in life learn in school. There are different subjects that you can find where you can teach your infant. This way when they get to the age of going to school they will shine out with more than passing marks in school which will make you as a parent very proud.
So you should start out with a book like Calculus for Infants. Funny thing is, if your infant truly understands the concept, it will learn a mathematical concept that is hard for many to grasp. However if your child starts early they would be able to master more advanced Calculus later in life that is required for degree in which the child is perusing.
So start early with your kids.