You'll have hours of fun building and playing with these wooden marble run kits. These models are a bit more challenging than other Robotime kits because it is important to align everything well to ensure a safe journey for your marbles. The overall feedback of the quality of these kits has been excellent, but we feel you should be aware that unlike other kits, more patience is required and an understanding that sometimes you have to improvise to get things working perfectly. The minimum recommended age is 14, but if this is a gift for the young engineer in your life, we suggest you make this a project to build together. We've built these with our kids and the experience is far greater than you'll ever get from TV!