Intergalactic P.S. 3

"Charles Wallace Murry is old enough to start school, but his sister, Meg, and their friend Calvin know he isn't cut out for classes on Earth--Meg worries that he'll be more misunderstood than ever. Luckily, with the help of the three celestial creatures Mrs. Watsit, Mrs. Who, and Mrs. Which, there is another place where Charles Wallace can get his education: Intergalactic P.S. 3, a public school in a different galaxy. The three children travel through time and space to reach the school, but to earn admittance, each must pass an unusual exam. Meg's test will challenge her inner strength, her perspective, and her ability to protect the ones she loves"--Provided by publisher.