4WD OffRoad Vehicles Stem Toys with Instruction Book. The 4WD OffRoad Vehicles Kit lets kids build a rugged, highperformance model while exploring the basics of mechanical structure and motion. The assembly process strengthens spatial reasoning, problemsolving, and fine motor skills as children follow the included instruction book. Once built, the vehicles bold design and sturdy wheels make it perfect for imaginative play. A great choice for young engineers and car enthusiasts.