"Leo teaches his cat Pallas all about lines by applying his knowledge of geometry to their Stone Age world. Funny illustrations and stories provide a humorous introduction to math concepts. Leo explains the significance of points and how many points together make up lines and segments. Information boxes accompany each story to explore real applications of lines in the natural and designed world."-- Provided by publisher.

Straight lines : point to point -- Line segments : lines that end -- Line-up! -- Horizontal lines : horizon -- Vertical lines -- Lines that enclose : lines as borders -- Intersecting lines : which way? -- Measuring lines -- Parallel lines -- Criss-cross -- Number line : going below -- Lines in nature -- Angles -- Rays on and on.