Might help the young'un to look at mvements in art rather than concentrate on a list of names. From a schoolchild's viewpoint, this means broadly examing the Pre-Raphaelites, the Impressionists, and society portrait painters such as Sargeant.
That way you can pick out a typical work of each genre and the child can easily describe their main differences in their own language.
But nothing beats seeing the real thing - depending on where you live, the art galleries of our major towns are a treasure trove of these paintings, and free to go in.