We've been sent 2 of the brilliant build-it-yourself cardboard science kits from Newton's Lab to review. Made by Kikkerland, they are very carefully designed build-it-yourself physics-based engineering and science kits suitable for older children aged around 10 or over. 

I'm really keen that toys should last for decades, or be made with the Earth in mind (or both if possible). Children's science kits often include throwaway items, or tons of plastic bags, and you end up feeling like you might well be a part of the problem. The Newton's Lab kits are very much recycled cardboard with a couple of other pieces for stability or durability, packaged in a recycled cardboard box.