I forgot to mention the I have APE ver 7. 8o)
Check out my free article on Basic Keyframing at Muvipix.com. It's a bit dated, but it shows you the basics.
My latest book not only includes step-by-step instructions for doing this, but also includes instructions for creating a 3D zoom look as well as nearly 50 other special effects.
As Steve states, this is done via Keyframing the fixed Effect>Motion>Position, and for a Zoom, Effect>Motion>Scale. You can alter the speed of the Zoom, or Pan, and can even alter the Velocity (how quickly it starts/stops) with Bezier Curves on those Keyframes.
Steve covers Basic Keyframing well, and I highly recommend his instruction series.
Here is another TUTORIAL, but it is for an earlier version of Premiere, and not PrElements.
PS - Keyframing is a bit abstract at first, but once one gets the hang of it, they'll find it so very useful for animation needs.
Woodsyl, when you say "pan in on still pictures" I take it you mean zoom in. pan refers a side to side action, This is done in the motion effect that is on each clip by default, you don't have to add it. Select clip, go to effects, open motion (turn triangle down) then you can select scale and or position. To animate position CTI (red line) at start point then click stop watch. Move CTI to new position and make changes to scale and position. Hope this is some help.
P.S oops, just remembered you have PE7, I started in CS3 so this may not be correct for you. Not my first mistake today.
The Effect>Motion>Scale (Zoom) and Motion>Position (Pan) are very similar in PrE. As of PrE 7, Adobe has enhanced the Effects Control (Edit Effect in PrE), so that it is closer to what PrPro offers. You are very close.
Thanks for clarifying the differences between Pan & Zoom, as I had missed the OP's wording. I think that you are correct in interpreting what is actually needed. Animation of either is virtually the same, just Scale vs Position.