A modern-day video of an old psychology experiment.
Yes it was a test done in the 1960s that followed the kids from adolescence into adulthood. The study showed that kids that couldn't wait would develop a higher body-mass index and struggle with drugs.Via Neatorama. Cute.
The key is that it shows which kids are able to think about something other than the marshmallow, which in turn shows which kids will give into things such as peer pressure.