Free for schools. Aligned with the Common Core Standards used in most states (or state curricula where applicable). Full of video tutorials.
Did I mention free?
TenMarks offers public school teachers free accounts for their entire class. Once you’re set up, you can provide log-in information to parents and assign enrichment math activities, starting with first grade and ending with algebra 1 and 2 as well as geometry.
Below is an example of the tracks, or short units, for grade 1. All questions are multiple-choice–a natural choice with today’s testing regiments–which allows the TenMarks system to score automatically and send the teacher reports of where each student stands.
When assigned 20 practice questions, at this level, at least, the items get redundant (the same question again). 10 questions are probably sufficient practice.
The score reports give the dates, the time on tasks, and a record of any aids used.
Overall, TenMarks is a solid entry into the online math enrichment arena.