Chemistry Tic Tac Think. A Differentiated Writing Assignment. In this menu choice board activity, students choose a task from each horizontal row. Students have a choice, but the first row is related to the history of chemistry, the second to the periodic table and the third to the elements. In some cases, you may want to specify certain tasks for individual students or challenge some students to complete all the squares for enrichment. Use in class or as a homework assignment. Includes a writin