Take the old fashioned fun of a stacking block set, cross it with interlocking legos, make it tube-shaped and add pretty marbles... and you'll have some idea of the hours of fun kids can have with this toy. The kit comes with a variety of colorful angled tubes that fit together, supported by a triangular stand. Some are plain, others have extra doodads like little wheels or twists. The components, while manageable, present an excellent and surprisingly rigorous logical challenge for a five-year-old's developing brain. And that's just a start: expect squeals of delight once you add a marble, or two, or six. Count on this toy making you and your kid smile for a good, long time. (Toys 'R' Us, $19.99)