Started in August 2011, Power Academy is a Forumotion roleplay forum centering around the eponymous boarding school for teens with superpowers. A freeform tale of action, adventure, romance, comedy, drama, and tropes. Lots and lots of tropes. There's a character page here.Found here.
Apocalypse How: Alice and her family grew up in a hellish, irradiated wasteland left over from a nuclear war, and Garrett mentions that a huge zombie epidemic broke out about 30 years prior—about a Class 1.
Bigger on the Inside: The Rec Hall. Any room can be generated instantly upon opening the door based on what the guest is imagining. Want an Olympic-sized swimming pool? Bam, you have one.
This applies to the forum in general; over time, rooms and areas are added as needed.
Bizarre Seasons / Empathic Environment: Over the course of the first three days, Power Academy has experienced a warm, sunny day, a snowy morning quickly turning into an overcast day where the snow melted, and a rainy day. Consecutively.
Although the later retcon about time's passage, with each "day" being a sort of montage of the events of a week, causes the weather to make a little more sense.
Cast Full of Bi: Played with. At the very least, there are very few characters who fall into either of the extremes on the Kinsey Scale. Aside from the multitude of bisexual characters (male and female alike) in the story, including those who mainly interact with the opposite sex anyway, there are a lot of otherwise purely straight or gay characters who tend to have exceptions. Individual sexuality is still acknowledged, making this distinct from Everyone Is Bi.
Everybody Has Lots of Sex: On the second day in-universe, but eventually dialed back when things became a little too predictable. Can be justified, considering the student population consists primarily of teenagers, whether they're finding true love or blowing off steam.
The users' humorousrationale was as follows: "Snow Means Love, the snow started melting from the sun, heat and the sun equal sexuality, therefore melting snow equals libido."
With some characters in-story, it also seems to be deconstructed; Tala, Wendy, and Bethany are all quite fanservicey, but were artificially created to look the way they do (by male creators, no less)—a fact that haunts them to no end; breaking free of the roles set for them is a big part of their character development. See also the Alternate Character Interpretation for Lightning.
Five-Man Band: Dr. Archer gives a lecture on the trope in Team Relations 101.
Foe Romance Subtext: A triple example: Swilium originally created Wendy as his new girlfriend; she eventually turned against him. Later, she reveals to Isaac that she was modeled after Tala (who also turned against Swilium), herself an Opposite-Sex Clone of his rival Talan.
This is pretty rampant throughout the story, with other examples including Helena/Talan and Warpen/Valerie.
Leaning on the Fourth Wall: Isaac comments on the fact that it's snowing on the second day: "Right now, it's at the end of summer, supposedly. Then again, for some strange reason, it does feel like we've already been here for months..."
Bottlecap mines and bottlecap knuckles are among Gill's inventions.
In addition to Willow's jumpsuit being blue and yellow, the serial number on the back reads v101-3.
Talan's combat armor is based heavily off of N7 armor.
Trim's spell incantations are taken from Zatch Bell
Lightning is shown to be the resident Pegasister, wearing a Pinkie Pie-themed t-shirt at one point. And in the Visitors From the Future thread, Isaac verifies his future self's identity by asking who their favorite of the Mane Six is (answering with Fluttershy).
She is also shown wearing a Pokebra to seduce Talan.
Adrian's repertoire of poisons includes Nova-6, and he later works on a potion that replicates Titan.