FunnelBrain is an interactive online learning website. It is difficult to find websites with Algebra skills that allow the students to be interactive. This website has flashcards for factoring and foiling and system of equations. When students are practicing with the flashcards the time they spend on each flashcard is recorded as well as how many answers are correct.
This is a website I would use with students in the computer lab. This would allow me to assign individual students the flashcards with the concept they need to work on.
The website can be found here.