I came across this site looking for materials for a Math Workshop. You’re most likely going to be putting textbook or practice/reteach pages in your Independent Practice station, but if you are doing a review or are looking for a place to find extra review problems, this is a great site.
If you want an ad-free version you have to pay, but the ads really aren’t that bad and you can access all of the information for free. You can create your own worksheets with various options, including answer keys. This could also work for your fluency station, as there are options to print out flashcards as well.
I definitely think it’s worth checking out! The site can be accessed here: http://www.math-aids.com