Gift Certificates Coupons

I’m a dance instructor with a private studio and was thinking of passing out gift certificates for private lessons I teach. I don’t teach large classes so I’m trying to attract students by marketing. I was thinking of doing $50 gift certificate for the first lesson and they pay the remaining cost of $15. I didn’t want to do free lessons because I’m worried about those who only want to take advantage of a freebie deal and that’s it. Do you have any other great ideas on how to attract students for dance lessons using gift certificates. I’m open to suggestions on amount of $, what good ways to distribute them, conditions & terms I should put on the certificates and any such advice that could be effective and helpful. (No wisecracks needed.) Thank you for the advice and help!