Using Up/Down Over 10
Using Up/Down over 10:
When adding, students take one number (usually the larger number) and leave it whole, and take the other number and decompose it to make 10. The remaining amount is added to the ten that was made.
When subtracting, students decompose the smaller number to subtract an amount that leaves 10 remaining. Then the students would subtract the remaining amount to find the difference.
Videos for Educators
Important Information:
This strategy is the beginning stages of decomposing numbers. Students who use this strategy are comfortable with making 10. It is important that students practice making 10 using addition and subtraction. For example students should be comfortable using 0-10 to make ten using addition as well as using 10-20 to make ten using subtraction.
Deliberate practice decomposing numbers will be important before introducing this strategy to students.
Using ten frames will be beneficial to all students while working with this strategy.
Examples of what students might do
Examples of what students might say:
"I know how to make 10 with 8 so I took 2 from the 5 to make 10. I then added the leftover 3 to get to 13."
"15 take away 5 is 10 and then I took away 1 more to make 9."
Strategies to Support Student Learning
Students would benefit from using 10 frames to support the development of this strategy. By using the ten frames to join two amounts, while connecting the numerical version of the adding (or subtracting), students will be able to gain a stronger grasp of this strategy.
Once students are confidently using this strategy, encourage them to use the strategy with larger numbers. For example, students could add 350 to 90 by taking 50 from the 90 to join it to 50 from the first addend. This would create 100. Once the 100 is joined with the 300 to make 400 the remaining 40 from the second addend can be joined.
Things You Can Do In The Classroom
Games (Click Links Below)
Students race to identify the missing part of a whole. (Lawson, Pg. 180)
A strategy game where students practice taking jumps of 10 forward and backward. (Lawson, Pg. 181)
Players practice taking jumps of 10 forwards and backwards and one more or one less. (Lawson, Pg. 182)
Players take turns drawing cards which require them to walk or slide jumps of 10's or 1's.
This game promotes the foundation for strategy of up/down over 10. Students work on naming all of the pairs of number that make up the target number. (Lawson, Pg 169)
Students work on determining what numbers make 10 and then keep the remaining number (change) for points.
Players try to make ten by matching a card from their hand with one of the four cards placed in the middle of the game space. Players continue to take turns until all cards have been dealt and played. (Lawson, Pg 174)
All games and activities located above are directly linked. Some can be found in the Alex Lawson What to Look For Resource. Page locations have been included in the description of each activity.