Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
Teaching 10 more and 10 less can be a tricky standard. The hardest part of the standard is that it requires students to it mentally. The word mentally is a key word here. This unit will help your students reach that objective by scaffolding the way there.
This is a three part unit that slowly takes away the hundreds chart and will prepare students to do this work mentally.
Crosses on the Hundreds Chart……. 6 worksheets
These worksheets are used to introduce the concept of 10 more, 10 less, 1 more and 1 less. The hundreds chart takes up most of the page and students spend time working with the hundreds chart. This should be teacher lead the first 3 or 4 times.
Crosses with mini Hundreds Chart…. 6 worksheets
In these worksheets, the hundreds chart is taken out of focus and the focus is thinking about a number and mentally adding and subtracting. The hundreds chart is still there for support, but it is small. You can also have the students check their work by coloring the answers on the mini hundreds chart
Chunks of the Hundreds Chart……… 7 worksheets
The complete hundreds chart is gone and there is a tiny portion of the hundreds chart to look at. Students have the support of the hundreds chart but in a minimal way. The students will also be writing math sentences as well.
19 worksheets in all!
1 assessment with 2 different looks.
Learn more about this unit at my blog!