Think-marks are bookmarks that can be used during Reader's Workshop. These are great for students to write vocabulary words on. Individual students or different students can add on to them each day. I used them to teach reading across the genres. Students were divided into three groups each with a basket of books of all genres, on one topic. Students wrote vocabulary words during independent reading. Then shared their words with each other when we came back together. They discovered that many of the vocabulary words on their topic were the same, even though they were in different genres.