Build it! Subtraction Fluency
Lesson 4 of 4
Objective: SWBAT to set up, record and solve a subtraction problems to five by rolling dice to create, record and solve the subtraction problems.
Today's calendar and daily counting review begin with our standard elements of daily calendar, counting to 20, counting down from 20, counting to 100 by tens and ones. Here are the videos I use to get kids excited about counting.
Here are the video we use to count:
Countdown from 20:
Count by tens:
Count by ones:
Dance, sing and exercise your way to fluency! The kids love it!
I have the kids sing their favorite subtraction song, When You Subtract with a Pirate. We discuss what subtraction is and how it is done.
Next I flash the subtraction cards (0 to 5) to build fluency. They answer as quickly as they can. My lower-achieving kids are not fluent at it, but they learn from the higher achievers as they are repeatedly exposed.
I then demonstrate how the activity is done. I do it a couple of times with the kids just watching. On the third round I have the kids tell me what they think comes next. They instruct me on what steps to setup, record and solve the subtraction problems.
Now it's the kids' turn. I assign them into partners. The partnerships are strategically planned. I partner high kids with med-low kids and med-high kids with low kids so they can learn together without causing frustration.
I guide the pairs step by step through the first several rounds of the activity. The most difficult thing to get them to understand is that the larger number must come first in the subtraction problem as it is the whole number.
Once the kids start jumping ahead or immediately tell me what comes next to get me moving faster, I begin releasing the activity to them for independent practice.
I start the release by having them tell me what step comes next with each part of the activity.
1) Roll dice.
2) Put dice in order to make a subtraction problem.
3) Record equation.
Once the kids are able to take on the activity for themselves, I let them go on their own while I roam the room and monitor for any pairs that need my assistance. I sit with any teams that show misunderstanding and continue to guide them through the process.
As I roam, I ask the students to explain to me how they are completing the activity. I want them to be able to tell me that the large number has to go first, then the subtraction sign, the small number and the equal sign. Then you can subtract like this, "...." (They explain in their own words).
When time is up and the supplies are put away, I have the kids gather back on the floor to discuss the activity and what they learned. I also ask them if they have any suggestions for how we can improve this lesson or use it again in the future.
All ideas are recorded on chart paper and I try to consider future use ideas they may have, as this deliberate attention to student thinking creates buy-in and makes the kids want to participate and learn (ownership for learning).
The exit ticket is a quick six problem subtraction page (two tickets on one page - copy and cut in half). They are already formatted in the proper notation.
The reason I ask the kids to setup the problems during the activity is because I want them to gain the conceptual understanding that when subtracting. I want them to understand that you must have a quantity greater than the one that is being taken away. I do not test them on that. I just want to know that so they can efficiently solve subtraction problems on their own.