Not understanding the meaning of a sentence

Oct. 7, 2017 (Chapter 14 Comprehension Problems in my book)

Today I was reading something on social media and this is what it said, “Every Friday afternoon Mary's teacher asks her students to take out a piece of paper and write down the names of four children with whom they'd like to sit the following week.” For some reason, this sentence was very confusing to my brain! I had to read it several times to figure out why.

This is what I have figured out. If I was a teacher and I needed to tell my student's this sentence, this is the way that I would say it so that “my brain” would understand it. “Every Friday afternoon Mary's teacher asks her students to take out a piece of paper and write down the names of four children that they would like to sit with next week.” For me, using the words “with whom and they'd “confuses my brain.