There are also versions where students subtract 10 and 100 down a number line, too.One of the skills students need to be successful on number lines is the ability to make jumps of 10 and 100. This student started at 15 and counted 35 jumps and then took one away at the end.
This is a whiteboard sheet that we go through daily.
The number line at the bottom helps students solidify their understanding of both how to use a number line and how “make 100 or make 1000”. In this activity, students practice making jumps of 10 and 100 up a number line.
It’s a learning process and something I’m continually reflecting on throughout the years.
All that to say, you may see a few things labeled one way and question its label.
We spend a lot of time discussing a variety of strategies, using many different models, and doing mental math. based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method.
Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
The thinking, or what students do with the numbers, is the strategy. In all honesty, I’m not always consistent in labeling something a strategy or a model.
I try to be, but like you, I’m human and sometimes mix them up, especially when I’m in the moment with students.
Are you interested in a free sampler of some of my Two-Digit Addition and Subtraction Products?
are how the strategies are organized on paper so that students can explain or see the strategy.