Characters in episodes are bandaged, they have bruises, a small cut on their bloody lips and broken bones.
Sam is shown assaulting numerous people (mainly Freddie)
Blood is shown on several occasions, but always in a comedic manner.
Sam can get pretty violent when irritated or angry
Much of the violence is mild comical slapstick violence. Characters are knocked down, beaten up, shoved down to the ground, hit with props/objects and thrown across the room (this is for comedic effect) Sam is a brutal and belligerent fighter, always eager to brawl whenever necessary. She usually resorts to punches, kicks and slaps.
The episode iFight Shelby Marx might seem violent (Carly has to fight another girl "for fun"). We see Shelby fighting Carly and another girl, but the violence isn't very realistic.
Sam hits people with a sock full of butter in "iTake On DIngo."
In a few episodes, Chuck bullies and beats Spencer up.
In several episodes Sam electrocutes other people with a shock pen making them faint.
The episode iGet Pranky is about Spencer pulling pranks (some mean, but not major). Once, he used some garlic powder to fall on all the kids in his school when he was a teenager and it burned their eyes.