This is a book in a collection that try to bring science theory and an experiment to do at home at the end. The theory is good, well explain, easy to understand and with an appropriate vocabulary. The problem is the experiment part. A very very basic experiment, you can find way better stuff to do on those subject on the Internet, that a big fail on this part. 5 stars for the theory, 1 stars for the experiment, I'll go in between with a 2,5.