The lesson: The only way to get what you want is to be innovative and determined. Sometimes this will involve magic keyboards. However, with great power comes great responsibility, and if you're going to use your magic keyboard to go to the moon make sure you bring spare batteries.
The lesson: "Out of Order" signs will not stop anyone. If you know that you have an arcade machine that can summon devil-esque creatures, make a sign to that effect. It's like the way I label my bottles of alcohol and jars of Nutella with the message "touch this and I will gouge your eyes out xoxo."
The lesson: People may think that this episode could be taken as a lesson on how you shouldn't drink too much caffeine, but I beg to differ. Things only go badly once they drink chamomile tea.
The lesson: Only bad people have mullets.
The lesson: If someone doesn't want to celebrate their birthday, respect their wishes. Or else you might end up destroying their eternal youth.
The lesson: If you don't know how long the hot dogs have been in the freezer, they're probably evil.
The lesson: Grilled cheese sandwiches actually solve EVERYTHING.
The lesson: Bros before hoes is really really stupid.
The lesson: Eighties clothes are a fate worse than death. Keep this in mind for the next time you need to get revenge on someone.
The lesson: Accountants are way more badass than we give them credit for. Audits are way more intense than you would think. Hugs solve everything.
The lesson: Too much junk food and excessive exercise are both not good for you and will result in life as a gelatinous blob.
The lesson: People will like you if you're cool and in a band. People will like you even more if you banish your douchey future selves who lip-sync and pretend to be cool.
Episode synopses taken from Wikipedia