The Sam's Science series (see Maynard, above) introduces Sam, who has a cold, and who sneezes; his mother explains why he should catch his sneeze in a tissue--a germ from a sneeze can spread up to ten yards, ""as far as three elephants standing in a line."" Sam and his mother discuss how people get colds; how the body fights germs; the components of blood, including white blood cells that zap germs and eat bacteria; how scabs keep the bacteria out, and much more. While they talk, Sam imagines the white blood cells as smiling white cotton balls with striped legs, running after the toothy orange germs, the chicken pox virus has spots, while the bacteria, which McEwen shows as pickle-like and with legs, is running from the white blood cells. Rowan packs a lot of information into this useful title, enhanced by the humorous illustrations. It's a lively and inviting introduction to colds and germs--and science--for the sniffle-prone picture-book set.