Edward Barnard is right. Your use of the word "this" makes your meaning unclear. Another alternative (besides the one Mr. Barnard gave you) would be to say:
"I will try the Thursday afternoon class and see how it works out." Your use of the future tense works in that sentence.
If you were to say, "I will try it, if it will work," you would be clear in meaning, but your logic would be off. When you say you will try something or try to do something, you are implying that you aren't sure if it will work or not. You don't know if it will work until you do try it. If you already know it will work, there is no doubt in that case. So it's important to get the tense right, but it's also important that your sentences make sense and show good logic.
Another possibility if you want to use "would" is to say: "I would try the Thursday online class if I thought it might work." Or you could say, "I would try the Thursday online class if thought it would work."
The word "would" is not really a "tense." Tenses refer to time. Words like "would" express doubt or possibility.