For different reasons, but I feel like I paid for three kids and I only have two.

College costs are insane, and not just tuition. When my older child went to Purdue and I had to pay close to $1,000 for her first semester textbooks, I realized how nuts that whole textbook game is.  I'm a prof myself, and I decided to stop using textbooks. Now I just assign articles available for free through the university library.  More work for me to set it up, but I feel good about helping out families with these stupid expenses. And I think it increases the relevance of the class, absolutely no cost to the rigor of the educational experience.