Controlling MC from timeline by AS. Help! please

I have a MC in my movie. I want to control it’s properties in different frames in the main timeline.
For instance
at the 1. frame change it’s position
at frame 50 change it’s alpha
at frame 100 change it’s scale

until now I have done all this by motion tweening but I know AS is the best way.
Could anyone help me on this?

Thanks
mx-guest2004