If you are a lifelong learner or know someone who is, I recommend The Great Courses which are a series of college-level audio and video courses. The Teaching Company produces and distributes over 500 of them. Notable instructors and experts create the wide variety of interesting and entertaining lectures. The categories range from English literature, philosophy, science, photography, history, art, astronomy, health, electronics, etc. No exams, no homework, and no prerequisites are involved.
I enjoy the CDs so I can listen in the car during my commute. The videos can be viewed on TV, laptop, tablet, whatever is convenient. They are available through streaming and some are on Netflix. I receive their catalogs that offer discounts. The most recent one has 75% off on any order until December 4th. Or you can go to their website:
Photo from Wikipedia.org.