Various examples of the "Scale" transform are shown here...this is a great resource for teachers and students.

I've decided to build my own little After Effects Visual Reference Library for when I'm teaching my motion graphics classes and post it here. This is in no way meant to replace the books out on the market when you are teaching...It's more of a visual complement to them.

There are several scale examples below that you can play.

Some helpful shortcuts when dealing with Scale ( I'm doing these from a PC so the shortcuts might be different in some cases on a Mac...whenever it says CTRL switch that to CMND or Open Apple for the Mac )

S = Scale
F9 = Easy Ease or look under the menu: Animation / Keyframe Assistant / Easy Ease
Shift F9 = Easy Ease In or look under the menu: Animation / Keyframe Assistant / Easy Ease In
Ctrl Shift F9 = Easy Ease Out or look under the menu: Animation / Keyframe Assistant / Easy Ease Out
Exponential Scale needs to have at least 2 keyframes selected and can be found under the menu: Animation / Keyframe Assistant / Exponential Scale
J = Previous Keyframe
K = Next Keyframe
Home = Beginning of Timeline
End = End of Timeline

A. Jump to previous keyframe
B. Current keyframe at time marker "N". Add or delete keyframe at current time marker
C. Jump to next keyframe
D. Stopwatch: Enable property to accept keyframes
E. Stopwatch: Not Enable - will not accept keyframes
F. Scale property
G. Chain Link allows X and Y scale to change independently when unchecked or together when checked
H. X scale - horizontal 
I. Y scale - vertical
J. Normal Keyframe
K. Easy Ease Out keyframe - slow out of keyframe
L. Easy Ease keyframe - slow in and out of keyframe
M. Easy Ease In - slow into keyframe
N. Current keyframe at time marker

A. X scale node
B. Y scale node
C. XY scale node. To constrain both X and Y scale you must hold down shift

A. Exponential scale
B. Normal scale

A. 0%
B. 200%
C. Normal scale represented in the graph editor
D. Exponential scale represented in the graph editor

If you would like to use this After Effects project you can find it HERE

X scale is a horizontal scale. The chain link for scale must be deselected for this to work if you are scaling from the timeline.

Y is a vertical scale. The chain link for scale must be deselected for this to work if you are scaling from the timeline.

XY scale is a constrained scale. The chain link for scale must be selected for this to work if you are scaling from the timeline.

Exponential Scale adds keframes at every frame to simulate a realistic acceleration of a zoom lens. You must have 2 keyframes selected for this to work. 

Easy Ease In starts fast and then slows down the speed of the layer going into the keyframe   

Easy Ease Out slows down the speed of the layer going out of the keyframe 

Scale Comparisons...these are posted to give you an idea of how the scale speeds would look for the various settings

If you would like to use this After Effects project you can find it HERE