There are many screening devices you should use before choosing classes abroad.
Before registration, contact the director/instructor with questions.
1. Ask if it is an immersion program. If they hesitate, ask what percentage of the classes are in the language. If they do not do immersion, you should be tempted to run. You might ask first about their methodology and see if it makes sense to you. If the teacher speaks the language, but doesn't insist the students speak it (even at the beginner level) that's a red flag-- find somewhere else.
2. Ask what extras come with tuition. Many schools abroad have dance classes, music classes, and culinary courses--all in the language you're learning.
3. Find out about accomodations. If you're with a host family, see how long they've been in the program, how close they live to school, how you would be getting to class, which (if any) meals you would take with the family, etc. It's wonderful if you can take at least one meal a day with your family!
4. Ensure you understand which level you will enter. If you already speak at a beginners' level, it's better for learning's sake, not to repeat and do a beginner course. However, only you know your time constraints and your objectives for studying abroad. You may prefer making friends outside the school and learning the language from them. You may have a host family or neighbor who will show you around...what great language and cultural insight they could give you!
5. Find out the number of students per professor/instructor. Generally classes above 10 students per teacher are problematic. If they have 10, ask how that large a number is supported by only one teacher.