Khan Academy offers a free self-paced course in math for students in grades 5-12 and beyond. It tutors students in everything from basic math skills and number sense to geometry, algebra, trigonometry, and calculus. The tutorials consist of videos, step-by-step learning problems, and practice/quiz sessions where students can ask for hints and view videos to review steps.
There is a coaching section where teachers, tutors, or parents can enroll their kids and monitor their progress. A pretest helps to determine where each student is skilled and what skills he/she needs to work on next. A graph displaying each module as not started, in progress, passed or mastered gives both coaches and students an overall sense of how they are progressing in their math skills.
These newest enhancements to Khan Academy make it one of the best free tools available for self-paced math learning, especially for middle and high school students and homeschoolers. Free registration is required to make use of the monitoring and progression tools. No registration is required to use the videos and interactives to learn discrete math concepts. This makes it useful for self-learning, for instance, when a student is absent from class and misses a math lesson teaching a new concept or skill.
For the newest available content, you may also want to subscribe to the Khan Academy channel on YouTube.