Common Core’s Mathematical Practice 2, Reason abstractly and quantitatively, calls for students to make sense of quantities and their relationships in problem situations. They are able to translate a problem context into models, numbers and symbols that they can manipulate; they can interpret the meaning of numbers, symbols and units in their work in terms of what they represent in the original problem. This collection includes mathematical tasks and problems that provide opportunities for children to develop reasoning in a variety of ways, and a tool for creating visual models of problem situations. A companion Professional Development collection includes resources to help teachers and math specialists understand the intent and scope of MP 2 and plan for successful implementation.