Is Invisalign Teen Cheaper Than Regular Invisalign?

There really shouln't be any significant difference in price. You must have all your permanent teeth to qualify for Invisalign Teen therefore you are similar to an adult Invisalign treatment. If you qualify for Express, you may have some savings there, but that would be more dependant on the complexity of the treatment (how long it will take and how many trays you require).
Many dentists believe the same as I do, that teens are more likely to lose a set of trays, or not be compliant with keeping them in 22 hours per day. This will extend the legnth of treatment, and losing trays will increase the cost, therefore, many dentists won't do Invisalign Teen without discussing the possibility of the increased cost.