Here’s a fantastic way to kill a few minutes better understand correlation coefficients: http://guessthecorrelation.com/
You’re shown a simple scatter plot and enter the correlation coefficient you guess to be associated with it. If you’re close enough, you get coins, if you’re too far off, you lose a heart. There’s even a two-player mode. Basic gaming stuff, but you also build an intuition of what those correlation coefficients we’re throwing around all the time actually mean.

There’s more, though. The game also serves (another) serious purpose: Omar Wagih is collecting the data to analyse how we mortals perceive correlations in scatter plots.