Lengthening or Shortening Objects In Animations

Hi all,

   Well I'm getting a little better at creating animations with motion studies, but one thing I have not been able to do is to get an object to lengthen (for example, if I wanted to make an animation of a building getting taller or a road getting longer).  Any tips would be more than welcome.  Thanks!!

                                                                                                                                                    ~Alex

SolidworksMotion Studies