Do your kiddos remember their commas? Mine do! (okay, most of the time) I don't introduce commas by telling the kiddos the rules. Instead, I have them come up with the rules themselves. I give them a Comma Hunt paper and with a partner, they search through books to find three different ways that they see commas being used by real authors. They try to find 3 examples to prove it is a rule. Then they try to come up with a rule to present to the class.
Once we discuss possible rules as a group, we create an anchor chart together. I have the rules printed out and cut out already, so that I can easily glue them on. We talk about the rules one at a time and the kiddos are THRILLED when they discover their rule is real! I use examples the kiddos give me to record on the anchor chart.
For the next lesson, students search through books to find one example of each rule being used correctly. They love this. It gives them a real sense of ownership because they were involved in "making" these rules. I tell them to make sure the authors used commas correctly, so the kiddo think they are looking for an author to make a mistake. =)
We leave the anchor chart up all year, and my little darlings refer to it often. Enjoy!