Rules of Capitalization...Again

Let me start off by saying, Quirky knows the rules for capitalization. We have been over them, year after year after year. She knows them and I know she knows them. What I also know
is that Quirky has a tendency to be careless when she is writing, even in her final drafts. So after reading through her paper and getting more frustrated by the minute at just how careless she had been, I decided I could complain and fuss, or I could make her do a review project. So what I had her do was read through her  handbook, Scholastic Guides Checking Your Grammar and Getting It Right, and once again take notes in her notebook. She then created posters using the Phoster App to explain what she had read. She worked hard and overall did a pretty good job. However, there is one mistake in her posters. Can you find it?