The vtech 5423 Marble Rush Building Set is an exciting toy that allows children to build their own marble runs. This set comes with three different levels of construction plans, each with varying levels of difficulty, to challenge and engage children of different ages and skill levels. The Color-coded blocks and easy-to-follow guide help you construct three different builds from beginner to advanced, or create your own. Additionally, the set includes 10 marbles that are 24 mm in size. The instruction manual provides helpful information on the components and construction plans, as well as answers to frequently asked questions. The manual also includes a QR code that can be scanned to access the construction plan for an extreme playset. The vtech 5423 Marble Rush Building Set is recommended for children ages 3-8, but can be enjoyed by older children as well. With its motorized launcher and light, the 5423 set is an upgrade from the 5420 set. The dimensions of the 5423 Marble Rush Building Set are 18″ x 7.5″ x 16″. Overall, this toy is a great way to encourage creativity, problem-solving, and imaginative play in children.