When I want to assess where our kids are at in school, or for the sure cure of boredom, I send them to ThatQuiz.org, where they can take a timed or numbered quiz in just about any math subject as well as in a few vocabulary and geography areas .
Registration is required so that your students cannot access their grades (or change them!).
That Quiz describes the site as…(bold emphasis mine)
The most complete math test resource on the web today with over 2 million graded exams to date and over 100,000* participating students. What we believe in: Clean, quality, easily accessible, educational software for every school and child regardless of geographic location or economic class. What we don't believe in: Games, advertising, fees, spam or gimmicks. That Quiz is free for educational use.
*these are 2008 stats; I'm sure they are much higher now!
Here is a screenshot of the available categories (click on it to view it larger):
How to Learn More: Visit the "About That Quiz" page
How to Get this Freebie: Visit That Quiz You do not need to register to use the site. Students never need to register, but a teacher may wish to so that he/she can view student results.
Go here to view tests that other teachers have created
For just about any grade
Subscribe to FreelyEducate here