Reply To: Lesson 4-2: Where Comparison Lives In Additive Thinking – Discussion

[Kristin Snell]

I’m realizing that I should do way more work with number lines. Many of my 7th grade students only have a partial understanding of the many uses of number lines. The standard algorithm is handy, but with the gaps in their understanding, they often make mistakes. The visual of the number line should help them move towards noticing mistakes that can be made using the algorithm.