M.R.
First of all, great job by wanting your child to be bilingual! It is such an advantage!
Videos and TV are great, but kids need the interaction to learn it faster. Great job in signing her up for a class!
As for the speed of learning, remember that not everyone learns at the same pace. I used to teach English as a Second Language and had 50 mins a day with my students. At that rate, and by being in an English-only classroom the rest of the school day, we found out that statistically, it will take a student around 7 years to be literate. Ofcourse, some would sooner, but that was just the average.
If you want her to speak it fluently sooner than not, you will have to immerse her in the language. If a change of sitters is an option, consider that. Take her to a Spanish speaking church once in a while. Don't worry, you'll find a lot of Bilingual parents! Make friends with latino families and have play dates.
If you attend class with her, take notes and practice what was given in class at home. Every day. Kids learn mainly by memorization and play. Kids memorize through repetition. Have her "play" in Spanish with you. Give her the opportunity to speak what she knows.
All in all, learning a language is a slow process. There are things you can do to speed things up, but all in all, it requires patience. Keep up the good work!