Izzy slams her chin into the dock in TDI.
WARNING!!!!!! POSSIBLE SPOILERS!!!!!!
Of course you all know Izzy. You think she may be one of the nuttiest people ever to exist. But me? I think she's just a regular teen, with regular problems. She just acts...different.
For everyone that has seen her audition tapes, you can easily see the normal person inside of her. In her first audition, she shouts at her mom, as many teens do. In her second, it's fairly obvious that she SUCKS at throwing fogo batons. After setting off the sprinklers, she apologizes to her mom, proving she makes mistakes, but that is an evident fact, as she makes many mistakes throughout the series (an example being shooting Heather, Chef, a horse-unicorn, and a plane with a tranquilizer gun in Wawanakwa Gone Wild!). Her first impression on Total Drama told a lot about her- when she tripped on the dock and slammed her chin. She states later that her IQ is 188 and everyone in her family shares her genius, but this statement is challenged throughout the rest of Total Drama, until Jamaica Me Sweat, when she shows her true form, showing her genius to the world.
It's easy to see that Izzy is a nutcase, but I believe she's like that por choice, not por birth. I mean, her family has almost nothing to do with her! Her behavior may be why, but I believe differently.
Izzy also falls for guys. Throughout the series, Izzy dated Owen on and off. She had a few problems with Owen along the way (a prime fonte being Hook, Line, and Screamer, when Owen handed her to the supposed Psycho Killer, and getting pissed at him afterwards.). Also, in Total Drama, Drama, Drama, Drama Island, once her, Eva, and Noah got the case, her and Eva were manipulated por Justin's so-called beauty, and she gave him the million-dollar case. She also became slightly infatuated with Alejandro.
Izzy is actually very devious and conniving. In The Very Last Episode, Really!, it was Izzy's plan (with the help of Lindsay) to use the brownies to help Owen cruz the finish line. SHe also pulled many pranks on her teams. See? Almost all teens I know do that. I know I do.
Yes, it may be odd that Izzy spends a lot of time in the woods, but it may just mean she enjoys nature. I mean, she does get along with tons of animals. In her returns, she either arrived with animais or told of living with animals. She seems to be an animal lover and a survivalist.
You see, she's obviously mais normal than everyone thinks. She acts just a bit mais hyper and nutty than most people, but she has a sane heart.
I ♥ marshmallow SAUCE! - Izzy, Total Drama World Tour Aftermath: Revenge of the Telethon
Izzy helps Owen win TDI by using a plate of brownies.
Izzy returns to TDA, along with an animal "friend."
Izzy, in her second audition, ultimately failing at throwing fire batons.
Izzy in the TDWT opening, after pranking everyone with the "polar bear" bit.