Michael,
For moving letters about the page like that unless you want them changing from letter to letter as they move, I think particular is going to make things more difficult than they should be. Because of the need to precompose each letter and whatnot.
There are many ways in AE to accomplish what you want. From combining fractal noise with time displacement to Particular and what I would use Card Wipe.
Card wipe is a very useful tool. If your text is properly spaced you can divide up a precomp so that each letter is on it’s own slice. Don’t rotate them or mess with the Z axis, just mess with X and Y axis position and speed jitters -keyframe as desired-
See Tracking and Kerning in the character window of AE to get your letters spaced and ready for Card Wipe.
With this done in it’s own comp you can then track it to the notebook as needed without worry about the positioning of each individual letter in relation to the edge of the page.
Don’t forget details like blend mode and the font/size of the fonts being used to keep away from the student feel.
You can read this post about random letter generation if you think it to be helpful. https://forums.creativecow.net/readpost/2/922207
PS it sounds like a couple of quick and light defocus moves would make it seem a touch more realistic.
Hope that helps,
Ben