My new favorite FREE site for practice is below - Interactmath.com
This is a great resource for Algebra students and (for some content) PA Core 8 students as well.
Choose "Enter" and then choose *Algebra 1 Common Core (2012) from the drop down list
After pressing submit, you'll be presented with a list of topics aligned to our textbook. It's great practice for any sections you need help with, and it's free. You can do as little or as much as you would like and after every problem, you'll get immediate feedback on the quality of your work. Check it out next time you are looking for something a little extra.