I created this because my 9th graders sorely needed comma practice. It covers four of the most common usages for commas:
+To separate items in a series
+To separate two or more adjectives before a noun
+Before conjunctions for, and, nor, but, or, yet, & so when they join two independent clauses
+To set off nonessential clauses
There is a one-sided reference sheet that explains the rules, and gives examples.
There is a one-sided practice sheet that has students implement all of the rules, including a review section where they write their own sentences.
You may want to double-side this, and have students keep it in their binders, as it requires them to use their own paper for the practices.
If you are looking for expanded grammar practice on commas, colons, and semicolons, check this product out: Commas, Semicolons, and Colons Review
Teacher in the Rye