Colorful picture books and storybooks, a summer reading roundup; The President's Car, by Nancy Wilson Parker, New York: Thomas Y. Crowell. $8.95 .

Have you ever wondered what kind of "car" George Washington used when he was president? Or when the Secret Service was first used to guard the president and his family? Through the text and detailed illustrations the author describes the carriages and cars used by American presidents. The freedom enjoyed by the first presidents, who often drove their own carriages around Washington, D.C., contrasts sharply with the tight security used today to protect a president when he leaves the White House. Also, the gradual development of presidential protection, now the job of the Secret Service, is explained.

"The President's Car" is an amusing and very instuctive book that not only contains information about presidential vehicles, but also details about the presidents' lives and the gradual societal changes that have taken place since George Washington became the first President. This book will not only be of interest to young car enthusiasts but to those interested in the changes that have taken place in American styles and tastes over the last two centuries.