I've been looking at mathematical problem solving problem sets all summer and adding to my collection. I love Dr. George Lenchner's books and was told that Kangaroo Math USA had similar sets of materials available. For $10.45 I received two stapled together pages of 24 questions and solutions from Kangaroo Math USA. When I e-mailed the company to let them know that I didn't think two pages equaled a booklet and that I was disappointed in the value of my purchase I received the most rude replay asking if I were poor and couldn't afford to spend that much. If you're looking for materials, stay away from this group.