Ug
Raymond Briggs
 The book is about a boy named Ug living in the stone age who is thought by others to "think too much". He wants to have soft trousers (the trousers he and all the other cavemen wear are made of granite) and believes mammoth skin would be good to use, in the end, he and his father Dug do make the trousers, but after realising they cannot sew them together, they call it a day and leave them. Ug then grows up to be a cave painter as his mother Dugs warned him.