There is a cart with the Newton gauge attached to a large block of wood. This can be dragged to see the static and dynamic friction force on the newton scale. You can then add 1 or 2 kg on top of the block. Darien has found that the black table top works best.
There is also an adjustable ramp. The wood block can be placed at the top and the ramp raised until the critical angle. Measure it, wither with protractor or with meter stick and trig. There is a piece of rubber for the same purpose. Darien suggests trying shoe with cinder block as well.
There is the loop the loop track as well to show centripetal force, may be an additonal one as well, working on it.
Nate