Knol is focused on Study materials for school, College and University Education as well as for continuing education.
In this respect, there is a big scope for teachers and authors to post articles/knols/papers having practice problems in various subjects. Some of them can be given solutions in a separate page or in the same sheet. There is an effort to organize knol books by combing articles of various authors. Hence web pages having only problems also will get promoted as part of some Knol Books.