ditto...you didn't say which grade level. There are three books out in the Challenge Math series. There are not very many problems in the Primary Challenge book. He includes several levels, so you can start with the easiest and work your way up. There are 5 problems per level. In the other two, there are multiple problem sets for each chapter with many more problems to work.
Other possible resources to consider is the Hard Math series by Glenn Ellison, Cleo Borac competitive math books, MOEM books, and Beast Academy.
I wouldn't say that CWP and the Challenge Math series are similar at all. I find value in multiple math resources. Perhaps, your student would enjoy moving around topically in the CWP book and only doing a page of problems and looping through all the chapters to create breaks from similar type problems. I can understand being bored with working a series of volume questions day after day.
Edited by calbear, 18 October 2017 - 11:06 AM.