Through cozy conversation, just as they are about to devour pizza for lunch, Sam and his mother unravel the process of digestion in this entry in the Sam's Science series. Sam is childishly unscientific, but knows all about saliva and chewing and the tube that runs from his mouth to his stomach; with a little help from his mother, he covers such hard parts as the oesophagus and intestines. The plot line has an eager Sam reporting what he knows, involving much chewing and chomping, squishing and glopping, while his mother expands the discussion with clear explanations of bodily functions. A few Briticisms crop up, to no ill effect, and, while the measurements used are metric, they are defined in context. McEwen's clean-lined cartoons use the colors of a Crayola box, from school-bus yellow to tangerine orange. The typeface resembles a child's careful printing, underscoring the levity of Sam's responses and observations. He and his mother provide science at its simplest, with no small dash of fun.