Fossils, dinosaurs, and a sea cousin. Ancient animals

IS there a child who doesn't love dinosaurs? The fascination continues with each new school year, and two titles published this fall for young and middle readers have a lot to offer. Would-be marine biologists can also get an inside look at the world of rare sea turtles in another new book. The photographs in Dinosaurs Walked Here, by Patricia Lauber (Bradbury, New York, $15.95, 56 pp., ages 10 and up), are captivating on their own - full-color, well displayed, all-around superb. What's more, the text about fossils of ancient plants and animals, especially dinosaurs, is fascinating. Readers learn how fossils are formed, how they are found, and how scientists ``read'' the information they contain - like a ``diary'' of life on earth in times past. ``Reading'' fossils, we learn, depends on a knowledge of the rocks in which they're found, their geographic location and structure. At the same time, fossils help us to understand changes in the earth's surface, such as continental drift. There's much to explore here, conceptually and visually, and the only distracting element is the occasionally too-long captions for the illustrations.

Strange Creatures That Really Lived, by Millicent Selsam (Scholastic, New York, $13.95, 32 pp., ages 6 to 10), with colorful drawings by Jennifer Dewey, is a lively introduction to some of the curious - and enormous! - animals of the past. The easy-to-read text briefly and accurately describes the salient features and habits of ancient, long-extinct reptiles, fishlike sea animals, insects, and mammals. There are helpful guides to pronunciation of difficult prehistoric names, such as ``pteranodon'' (ter-AN-o-don); and a table of 30 animals at the back of the book, indicating the approximate times they lived and recapping their habitats, is a valuable resource. The book concludes with a simple but important concept for youngsters to learn about the conservation of rare animals - the need to ``give them space to live alongside us.''

Turtle Watch, by George Ancona (Macmillan, New York, $13.95, 48 pp., ages 8 and up), is another informative and likable book. It's a tale about saving rare sea turtles, whose ancestors may have appeared some 200 million years ago - long before dinosaurs. It's also the tale of two curious South American children who help an international team of scientists. As they develop a warm friendship with one young woman scientist, the children - and their readers - learn about the remarkable habits of the female turtles, which come ashore to lay their eggs in the sand. This true story, told with the help of sharp black-and-white photographs, sparks a growing concern for the endangered species of turtles in the local fishing community, and has a lot to teach today's worldwide village.

All three books are attractively produced, with first-rate illustrations, large, readable type, quality paper, and sturdy bindings. Each could be read aloud to a small group or enjoyed individually.

Sally Cartwright has taught elementary science and written eight science-related books for children.