Because you talk about meeting Jenny, a girl, I would suggest saying herself instead of himself in the first sentence.
but she couldn't remember or explain what to do next. She had lost the simplest of communication skills.
do you mean she couldn't remember how to explain it? Or she actually couldn't remember what came next.
I also was impressed with the hope
Maybe :I was also impressed ---- instead?
With this focus, I found academic success
With this goal in mind --- instead of with this focus? or --- focusing on this goal ---
sought to learn more beyond the classroom.
sought education beyond the classroom ---- maybe?
where I witnessed different therapies, modified barium swallows, and laryngeal stroboscopies
with "I witnessed different therapies" you seem to be starting a list, so maybe include "such as" before the different types
In addition, while assisting Lynn Spivak, Ph.D., the director of the center,
I would switch the role and the name here, "In addition, while I was assisting the director of the center, Lynn Spicak, Ph.D.,"
should it be "teachers
assistant" instead of "Teacher assistant"?
I perform ABA therapy in a classroom of children with severe autism.
"thereapy for a class of children with severe autism" perhaps?
Over all I like it, and it's clear you have a passion for the field. Good job!
It should be noted, I'm a highschool student, so my word is FAR from gospel, just some tweaks I would make if it were mine