Hi, @Chris Epstein!
I think kids always enjoy stickers. And filling out charts is also fun as well as a good visual of what has been accomplished. I would just encourage you to have space on the chart for attendance and maybe even for a student trying to learn a list so that infrequent attenders who haven't been there to receive the list of things to learn still get some sort of acknowledgment.
younger kids might also enjoy an extra sticker to wear.