I pay a little extra with my 8 week lesson series to get what my studio calls the "Goddess Package" which includes 8 "drop-in" classes, which are scheduled througout the week and have varying focus. I absolutely love having the option to go to those classes. The studio also has "Open Pole' time three times a week at no charge to lesson students.
We have Tricks & Transitions for those who know a lot of spins, but want to make things flow better. Flirty Flow & Freestyle, Floor Play, Spin & Teaz, Hottie Body, Cardio Pole, Sultry Chair, Sultry Pole, Video Vixen, etc.
The class card for the drop ins has an expiration date of 60 days, and many times it doesn't get added to your account until the second week of the lessons (unless you call and have it added sooner) so it normally doesn't expire until after you're done. This has come in handy when I had to wait a month for the next level to come around. I used my drop in classes during the weeks I had no lessons.
I know this is just the way my studio works and what works best for me and my body, but I wouldn't have it any other way for myself. Each class brings a little something different, as does each instructor. Don't be afraid to experiment with the different class types. I've learned so many different things by branching out and going to those classes. Of course, I can't get enough of pole. Plus, I've learned things in those classes that weren't covered in my lessons. It's helped me be more rounded.