Freerice.com is one of my favorite websites.
I discovered it in high school. Pretty much, you answer vocab questions and for each one you get right, 10 grains of rice are donated to an organization that aids developing countries.
Recently, they’ve added more quiz options: geography, German, art, chemistry, among others.
I like it because I can waste time and veg out a little bit, BUT I am learning and helping the world. Lethargy you can feel good about.