Watch I.N.K. Invisible Network of Kids (2009– ) full episodes online
Synopsis: Pinkerton School is a boarding school with two teachers. One of the teachers, Mr. Soper, is nice, and the other, Ms. Macbeth, is evil and is constantly trying to enslave the children of the school. However, four of the students act as a secret organisation known as “The Invisible Network of Kids”, or “I.N.K.” for short. I.N.K's mission is to thwart all of Ms. Macbeth's evil plans.
More information: IMDB, Wikipedia.