Most schools give teachers what is called a prep period during the school day. This is a period of time, often around 45 minutes, that teachers are meant to use to prepare for their lessons, grade, and do other non-teaching tasks during the work day.
However, teachers might not always be able to use this period for its intended purpose.
One reason why is a simple lack of resources, Tori Van Horn, a second grade special education teacher from Pennsylvania, told Business Insider.
"There are other teachers that have prep at the same time as me, so sometimes making copies can be tough," she said. "I have my own laminator at home because my school's has been broken forever."
A bigger issue, though, is that her prep period doesn't allow her enough time to really focus.
"I'm interpreting a lot of data and coming up with specific goals for my students to work towards," she said. "I find it difficult to jump into a big legal document for only 40 minutes at a time. I need to sit and focus to make sure I'm doing my best work."
And other times, teachers simply need a break.
"Sometimes I just want to sit during my lunch," Julia Van Ness said. "After teaching for four hours straight and then covering lunch duty, I know I need to take a few minutes and just sit there to let myself recharge. I would rather finish something at home than let myself burn out by 3 o'clock."