Design and engineer the tree house of your dreams with this one-of-a-kind building set. Use the included activity cards to complete engineering challenges. Build railings, platforms, trees, and then use your problem solving skills to re-engineer your design. Kids will love building their tree house—parents will love that they’re actually building critical thinking and STEM skills. Learning Skill: Engineering Recommended Ages: 5 Years And Up Measurements: 10.1 Length/Inches, 2.3 Height/Inches, 10.1 Width/Inches Assembly: Assembled Base Material: 100% Plastic Care: Wipe Clean Country of Origin: Imported p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 15.0px Calibri; -webkit-text-stroke: #000000} span.s1 {font-kerning: none} WARNING: CHOKING HAZARD – small parts. Not for children under 3 years.