Some other math coaches and I were having a recent discussion about whether it makes sense to include the number line in lessons introducing 6.NS.5. Here is the quote:
“We are wondering how much (if at all) to bring the number line into this lesson set [on 6.NS.5]. The standard feels focused on real world and less about the number line as a model. However, there is the reasoning that prior knowledge of a number line will help a student get a deeper understanding of 6.NS.5. But then 6.NS.6 explicitly mentions the number line.

6.NS.5:
Understand that positive and negative numbers are used together to describe quantities having opposite directions or values (e.g., temperature above/below zero, elevation above/below sea level, credits/debits, positive/negative electric charge); use positive and negative numbers to represent quantities in real-world contexts, explaining the meaning of 0 in each situation.

6.NS.6:
Understand a rational number as a point on the number line. Extend number line diagrams and coordinate axes familiar from previous grades to represent points on the line and in the plane with negative number coordinates.”

What do you guys think? Do you think the first quadrant all positive vertical and horizontal number line from 5.G.2 should be mentioned as prior knowledge in [a review] section? Do you think they should be presented with a numberline of positive and negative numbers in 6.NS.5 at all or should it all wait until 6.NS.6?”

Since several of us were wondering about this, I thought it would be useful to bring it to the forum.

Thanks for your help.