Both grades
Geometric figures: http://www.mathleague.com/
Proportions self-check quizzes: http://glencoe.mcgraw-hill.
Rags to riches: http://www.quia.com/rr/51667.
Arithmetic Four: http://www.shodor.org/
TAKS Blog: http://taksmath.blogspot.com/
6th Grade
6th TAKS online: http://ritter.tea.state.tx.us/
7th Grade
Percent equation: http://www.glencoe.com/sec/