Gr 3-5-This series blends a picture-book adventure with a bit of historical background, details about the scientific principles that are the focal point of the action, and directions to build a related project. In both titles, David, his huge dog Newton, and his friend Jessica are instructed by David's father, a creative inventor who helps them find the information and materials necessary for the object that they want to build. In Picnic, the trio constructs a blimp out of 289 balloons, a wooden rowboat, and some netting. Once airborne, they use some of the principles of blimp operation. However, the story mixes reality with fantasy, as the children drop anchor, spread a blanket, and eat lunch on a cloud, and youngsters might be confused about which is which. Facts about blimps and directions for a project using a milk carton and helium-filled balloons follow. In Super Salads, the kids put together a greenhouse. When they mistakenly use too much of the professor's special fertilizer, the plants grow so quickly that they explode, bursting the structure and scattering giant vegetables everywhere. A good history of greenhouses follows, along with instructions for making one out of a box. The cartoon illustrations feature bright colors and black-ink outlines. This combination of fantasy, fact, and educational experiments will work best with an adult's guidance, explanation, and supervision.-Karen Land, Greenport Public School, NY Copyright 2002 Cahners Business Information.