I would say that language courses are intense in the sense that when you take a language you take it many more times a week than an average class and there is much more information thrown at you to remember from a week to week basis. First year Spanish meets three days a week, and French meets Monday through Friday. Arabic, the language I’m taking, meets Monday through Thursday. (This may lessen as you get to a higher level, but this depends on the language, and usually happens during your third or fourth year of taking the language) So maybe the homework itself might not be intense for certain languages or certain professors, but you just have a lot more of it to do.
Most, if not all, language classes range from 4 credits to 5 credits. This is more than the average class, and in some cases, you are often told to count 5 credits classes as having the course load of two whole classes. Since they are so credit-heavy, you really need to make a big effort to get a good grade in the class. If you do badly in a 4 or 5 credit class, or even average like a B, it can still bring down your GPA or prevent it from going up even if you’ve done well in all of your other classes. This might be a big deal to those who are very GPA-conscious, and for those who are considering a heavier courseload.
Right now, I’m about to finish my second semester of Arabic, which I’m planning on continuing for the next year. It is one of the hardest languages to take at Barnard/Columbia, and the course is very fast paced, we usually get through a chapter/new vocabulary every 7-8 days. Additionally, there are some nights where I have to dedicate 4-5 hours just for Arabic homework. Arabic has taken up so much of my time, but it is an absolutely rewarding experience when I’ve learned something new. I don’t know if I could say Spanish and French are “easier” languages to learn, so just be in the mindset for any language class that you take is going to be fast-paced, have intensive learning, and be homework heavy.
Overall though, I believe learning a brand new language from the beginning is always going to take a lot of work, and you should definitely be prepared to dedicate a lot of your time to that. Languages are meant to be learned in order to be appreciated and used, so these classes are definitely not the ones you want to slack in! And most importantly, definitely choose a language that you know you will appreciate and enjoy learning, because with all the work and days you have to put into it, it would only be more stressful if it was a language you hated. Good luck! :)