I gave my grandchildren both the B&W and colored versions. They loved both.
I was looking for something to entertain a group of 11-14 year olds during a screen-free, mindfulness, crafting session. This activity was perfect as it engaged all abilities and the children were keen to challenge themselves. They work fine when printed onto paper or thin card. There are a range of levels from simple to more advanced. They all look impressive on completion, giving the children a sense of achievement and pride, as well as a finished product. An excellent buy!