Khan Academy
Instructional videos and practice exercises.
IXL Learning
Educational practice for K-12th graders in MATH, Language Arts, Science, Social Studies, and Spanish. IXL provides step by step instructions and solutions after incorrectly answering a practice problem.
VIDEOS
Finding x- and y-intercepts on the Calculator, TI83 & TI84 (00:00-3:10)
Linear Regression and Correlation (09:05)