Well, considering the economy of the mid 70’s thru the 80’s when her kids were in private school, 18k was pretty big sum compared to now.
With that being said, Warren threw money at the private schools based on the amount per year. As a person that didn’t even give a crap about her anyways, it doesn’t make her look like a person that sympathizes with the school system because she’s a parent. As Perspicacity mentioned earlier, it makes her look like her sympathy is a ruse because it’s what a union wants her to display to her supporters.