This is the best set of craft resources I've found, great whether it's for your own children or for working with children. Reasonable price, things you need for making things are simple and low in cost and if you're like me you can adapt the materials to make it a little bit different. Great for building children's self esteem; encouraging them to make something and seeing the amazing end result, that they made!
I use it in school at least once a week and before this I used things for boys to make and do Things for Boys to Make and Do (Usborne Activities)
until I gave it to my nephew for his 8th birthday and he loved it, not sure if he's made anything yet but he looked genuinely pleased. So buy anything in this range of books and you'll have guaranteed satisfaction. Ps. it's even more fun to makr something with them too!