How to make pictures smaller on the time line every time I lay one down.

Hello all!

I am very novice in the editing world.  So pardon my terrible question phrasing.  I am working on stop motion type material, and have been dealing with hundreds of photos.  I am wondering if there is a way to set the size permeantly smaller every time I put a picture on the editing line.  Every time I drop one it sets it about a second long, and I would like for most of them to be a tenth of a second.  Is there any quick way or is it hours of resizing in my future?  Thanks so much for any info! I hope the question is clear enough!