Same As Subtraction 9 & 10
Lesson 9 of 9
Objective: SWBAT identify equations with like differences by solving subtractions and gluing them in the correct difference column.
Daily calendar and counting practice is essential to gaining a strong number sense.
Calendar is an opportunity to develop a sense of patterns and ordinal counting (first, second, third...)
Daily counting practice develops number sense of what comes next, how units of ten build to 100, the concept of one more each time we say a number counting by ones to 100.
We use the ActivBoard to count. Before I had one, I used a standard kinder wall calendar and posters. Calendar and counting review is never missed in my room.
Here's the videos we use:
Count to 20:
Countdown from 20:
Count by 10's to 100:
Count to 100 by 1's:
Our most recently added counting video (for last quarter only) prepares the kids for counting by 5's to 100:
Remember to sing, dance and have fun, but have high expectations for those kids! Make sure they are saying the numbers and looking at them on the screen. Have them point to the board or screen as they count. Do not allow for someone to disconnect and do nothing. Be kind, but firm!
As always, we sing to When You Subtract with a Pirate:
We have a quick review of what subtraction is, what it means and how you do it. I have a couple of kids come up and demonstrate how to subtract using counting cubes.
I have the kids go to their tables (I count down from 5. By 0 they better be ready.) Materials are handed out and I begin the quick guided instruction.
Since we have used this format several times, they need a quick review and off they go! I guide them through one problem and let them go to complete the rest on their own. Quite a few kids can barely sit through that little of a guided instruction. They want to get going on their own immediately when they see the pages.
For some reason (the cutting and gluing, maybe?), they do not get tired of this format and want to do it all the time.
Since the kids are now very well accustomed to this format of solving equations and looking for those that have like differences, and the problems have become more complex, they need as much time as possible to complete the task.
I give them a solid 25 minutes to complete it as I roam the room monitoring progress and assisting students that may be struggling with the more challenging problems.
I sit with them at their table or, if there's more than two, I bring them to the floor with me for extra guided step by step instruction. I then have them do it on their own while they explain to me each step they take to solve each problem. This solidifies their understanding of the process as well as supports the conceptual understanding of subtraction because I require them to solve using counting cube.
What was surprising to me was the one table that outright challenged each other to accurately complete the job. The were not only looking for accuracy, but speed as well, which fosters the fluency we are looking for and they don't even know it!
I gather the kids to the floor once the floors and table are clean. I put a timer on while the clean the room. If they clean the room and put all supplies away within three minutes, the entire class gets points toward a fun class event. We are not allowed to have "parties" or movies so a fun class event is usually some form of academic BINGO.
Once we are gathered on the floor, we discusses the successes and the challenges of the activity.
Since the equations have increased in complexity (kinder level, of course), the first thing they note is how much longer it took to finish the activity compared to the last three lessons. They also noted that it was easier to make a mistake on the higher level problems.
I ask them why they thought that and it led back to the key idea of organization and keeping track of your steps and manipulatives. Smart kids!
Some of my high achieving students were done fairly early so I usually have a color by number or fun math page to work on once they are done. This limits disruptions and distractions the other kids might have to endure if the quikies were done without a second job.
The exit ticket is the completed subtraction sorting (same as) page. As I collect it I look for kids who I didn't catch when I'm roaming.
Red flags include:
- Extensive miscounting
- Equations consistently placed in the wrong column
- Equations placed in correct columns without having been answered first (copying from a friend??)
When I encounter any of the above, I meet with the child one on one first to determine the problem. I have them demonstrate for me how they solved the equations. If there is evidence that the child is struggling, I meet with them one on one or in a small group to provide further direct instruction and/or guided instruction.