The open number line is not just a powerful tool for computation, but it's an amazing model for developing all sorts of mathematical concepts! In this episode Pam and Kim discuss how to help students develop the open number line in a natural and meaningful way.
Talking Points:

• What is an open number line vs a closed number line?
• Are number lines, closed or open, discrete models and why does it matter?
• Why shift to a measurement model vs a discrete model?
• What are some common errors students make when we use the traditional way of teaching measurement?
• We suggest a rich task by Cathy Fosnot to help students develop an understanding of the open number line through measurement
• What can you model on an open number line? Elapsed time, addition and subtraction of whole numbers and integers and more
• Is an open number line helpful for higher math concepts?

See episode 138 for more about subtraction pitfalls

Check out Cathy Fosnot's amazing rich task:  https://www.heinemann.com/products/e01010.aspx