Yes, you will learn. Accelerated learning has been used since the '70s in this country and abroad and is a well-respected teaching methodology. The basic principles that are used include whole-brain learning for maximum memory and retention of vocabulary, as well as relaxation through visualizations and positive affirmations. These teaching techniques help you to feel comfortable, relaxed, and open to speaking and practicing what you are learning. Dialogues are taught with classical music.
Students work in groups and write role-plays which they perform for the rest of the class.
There are also many other group and pair activities. These classes have a conversational focus. You will learn a certain amount of grammar by listening to the dialogues and by writing role-plays, but grammar is not stressed in the course. You will be able to express yourself through the large amount of vocabulary that you will be learning and practicing. If you have specific grammar questions, however, your teacher will be happy to answer them during breaks and before and after class.