In 2015 I was looking for online short courses to do, to give me a taste of different academic topics. Whilst Google searching I came across Open2Study.
Open2Study is affiliated with Open Universities Australia, and provides a lot of online short courses on a wide range of topics.
And the best part is they're all FREE!!!
Although they don't give you a formal qualification, they can give you an indication of whether you like a subject or not, whether you are good at a subject tor not and whether you should pursue further studies in that field.
The short courses took me about 3 days to complete, and I was rewarded with a Certificate of Achievement which I proudly hang in my study.