Sorting by Size

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SWBAT understand how to sort objects by size.

Big Idea

Kinders love animals and in this activity they have a farm with animals of varying sizes and they got all mixed up! Their job is to sort them back into like sizes.

Daily Calendar and Counting Review

15 minutes

Each day we begin our math block with an interactive online calendar followed by counting songs and videos.

Calendar Time:

We do calendar on Starfall every afternoon.  This website has free reading and math resources for primary teachers. It also has a  “more” option that requires paying a yearly fee. The calendar use is free. A detailed description of Daily Calendar math is included in the resources.

Counting with online sources: Today we did counting practice to reinforce the counting skills. We watched two to three number recognition 0-10 videos (one to two minutes each) because some of my students students were still struggling with identifying numbers correctly in random order. We watched "Shawn the Train" and counted objects with him to refresh our memories on how to count objects to ten and to reinforce one to one counting. Since we have started the second quarter of the school year, we added to today's counting practice: counting to 20 forward and back, counting by tens to 100 and counting to 100 by ones to get a jump on our end of the year goals.


Direct Instruction

10 minutes

To begin this lesson, I use a Sorting by Attribute video to review what sorting by color and introduce sorting by size. I stop it when she is finished sorting by size. I save the last part of the video for the sorting by shape lesson.

I pause the video as we go to initiate discussion about how and why we are sorting the objects. This way the kids are actively engaged and thinking along with the video instead of just viewing it.

I ask students which group certain shapes will go in and why. We continue to view the video to see if they are correct.

You must preview this video so you can utilize it to the full benefit of the class.

Once we are finished interacting with the video, I take out a cup of sorting animals and demonstrate sorting them by size under the doc cam. I emphasize that it doesn't matter what kind of animals they are or what color. We are only looking for the same size.

When I am finished sorting my animals, we move on to the guided practice.

Guided Instruction

10 minutes

Each student is given a cup of animals (variety of kind, shape and color). This portion of the lesson can be done on the floor or at the tables. I prefer the floor the first time we do this together so I can quickly reach kids who may need assistance or support in understanding the concept.

I have the kids carefully and gently spill out the animals from their cup. I ask them to find a large animal and hold it up. I instruct them to lay it on the floor next to them and to pick up another large animal, any kind, and hold it up. I ask them to place that animal next to the first big animal. I repeat these steps for two medium and two small animals.

During this time I look for kids who need extra support or appear to not understand what they are asked to do. I as those kids to stay on the floor with me for further guided practice and I send the rest of the class to the tables where there are large containers of sorting animals.

Once I feel the small group with me has a clear understanding of how to sort by size, I have them join their friends at the tables.

Independent Practice

20 minutes

I ask the kids to sort the animals by size only. They are given the option to sort the tub as a table group or they can take a cup full of animals to sort on their own.

As the kids sort independently, I roam the room to look for kids who may still be struggling. I provide immediate support for anyone who is not demonstrating an understanding of the concept.

About half way into the allotted sorting time, I walk the room and ask students individually how they sorted their animals and if they can explain how they did it. I may ask extra questions for clarification or to encourage the kids to probe a little deeper. Extended questioning also challenges the kids' understanding and deepens their conceptual understanding about specific skills.

Please view the video below:


5 minutes

Once the allotted time is up, the kids clean up the materials and I ask one table at a time to join me on the floor for our closing discussion.

The closure is one of the most important elements of any lesson. Closure brings the kids' thinking back to the math and the skill goal. This way, the kids don't go home talking about playing with little animals, rather they go home and tell their parents that they were sorting by size. They focus on the what, how and why of the skill that is practiced.

We spend about five minutes reviewing what we learned. I ask them to explain what they did and how the did it. I ask them to explain their thinking. For instance, one of my students explained how she determined that a bunny and a frog were the same size. She explained that she made big rabbits, medium rabbits and small rabbits groups. Then she made big frogs, medium frogs and small frogs groups. She put the large rabbits and large frogs together. She then grouped the mediums together and then the smalls.