Transform matrix to scale children of a scrollview

I would like to make a scrollview that will scale the children based on their y coordinate (think the intro to the star wars movies). This means scaling the children based on their position in their parent. I know I can apply a transform matrix to them, but this is static, right? Is there a way to have it applied with a variable without just overriding the draw methods?

I guess I mean to apply a transform matrix to the node as a whole, not just within the node as with setAddtionalTransform()

Ok, I was just trying to do something stupid.

Best solution was to rotate the scrollview on the x axis in 3D.