Hi Krallu, in the model glider world, some gliders do not have ailerons but use dihedral wings and the rudder for turning... It works something like this...
Apply right rudder and the glider yaws to the right, pushing the tip of the left wing towards the incoming air. As the tip of the wing is at a high dihedral angle the air gets underneath it and gives it a lift. The right wing tip similarly gets pushed downwards by the airstream.
This method of control, which only uses the rudder, relies upon the wing having sufficient dihedral (say 15 degrees.) for it to work well. In a full size Cessna or Piper the dihedral is much less, so the effect is not so noticeable.