Who Will Choose the Sorting Rule?

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SWBAT sort shapes 3 different ways, determining sorting rules.

Big Idea

A flip chart on the Promethean board and laminated shapes keep student engagement high as they demonstrate their sorting skills.

Attention Grabber/Introduction

5 minutes

Usually, just seeing the Promethean board gets the kiddos fired up about math.  They just love being at the “big screen” moving things around!  I have the activity all projected up and ready to go before the students gather.

This time, however, I hold up little sandwich baggies filled with laminated, cut-out shapes of poster board in three colors.  Sometimes, students get less engaged when only one kid is at the Promethean board, so I made a way to keep all students engaged even when only student is working at the board.

Girls and boys, we are working at the big screen with sorting, but lucky you!  We also have baggies filled with these exact same shapes for you to sort at the same time!

This is what you will do:  open your bag and put the shapes out in any order near your tummy—just like the mixed-up shapes on the screen!  Be ready to move your shapes as we take turns moving shapes on the screen.

I’ll help pass the pen to all of you—but one of YOU will choose our sorting rule!

Guided Practice

30 minutes

Ten students are gathered on the floor of our “meeting spot” for this activity.  (You can also do this activity whole-class, with either a baggie of shapes for each student, which would be a TON of cutting, or you could pair students up and work in teams of two.)  My class for my intersession review week at my school is so huge, that this is just one of three activities going on.

I tell the kids, “As you get your baggie, follow the steps and show me that you are ready.  I will pass the pen [for the Promethean board] to kids who are ready to sort.  Okay…who is ready to make the sorting rule?!”

I watch the students open their baggies and set their shapes out.  I choose a student who has followed directions to quickly go up to the board and move the first shape out of the mixed pile and into its own place.  (Remember, if your Promethean board is mounted at some standard, big-kid level on your wall, a stool is really handy!)

One student moves a shape into what will eventually be a group.  Since we are reviewing and I want to seize the moment, I say, “Excellent start!  So which shape did she move to get us going?” 

Students respond, “A rhombus!”  [I specifically chose our trickiest shapes for this activity, just to get in a some extra shape review as well.  We have hexagons, rectangles (so often confused with triangles!), and rhombuses in 3 colors and 2 different sizes in our bags.)  I keep prompting until we get a thorough description, with the students ultimately saying, “A large, green rhombus!”

“Do we have a sorting rule yet?” I ask.  If one or more students respond “Yes,” I ask them to tell me the rule, and of course, they can’t.   “Hmm… Let’s keep working.  Who is ready to move the next shape?!”

A student who has already moved his large, green rhombus into its own group is selected to move another shape, while the other students are reminded to move their large, green rhombus into place.  This student moves a large, yellow hexagon into a different group.  We go over the description of the new group, and I ask again, “Do we have a sorting rule yet?”  Now, if the students don’t say something like “Color!  We are sorting by color!” or “Shape!  It’s sorting by shape!” we keep going, handing the pen to another student and repeating the process.

By the third shape moved, someone will announce a rule, which is fantastic. “Is she right?” I ask, trying to keep the emphasis on the kids.  “Yes!” they confirm, and I re-state the sorting rule.  “You have chosen to sort by Color!”  Excellent!  Now finish doing your sorts!”

As the kids move their shapes, I quickly move some of the shapes on the board, leaving enough for every student to move one shape into place.  As the students get their shapes sorted, I pass the pen from one student to another, giving everyone a chance to sort on the Promethean board.

When all shapes are sorted into piles, I ask, “Did we get our shapes sorted?” “Yes!” the students respond.  “What was the sorting rule?” I continue.  I choose a student to say “Color!”

Then it gets really good.  “Is there any other way to sort?” I ask.  The students respond, “Yes!”  I restart the Promethean board with the shapes mixed on the bottom while the students are directed to mix their shapes, as well.

We start the whole process again, this time with students sorting by a different attribute.  I remind students that they will be selected to sort on the Promethean board when I see they are keeping up with their sorting in front of them.  This keeps students focused and engaged, and by the end of the activity, we have sorted by color, shape, and size… with the students taking the lead.  It is exciting to truly be a facilitator and to stand back and see the learning that has taken place.


5 minutes

After the third sorting activity, I ask, “Did we sort our shapes different ways?” and the students respond, “Yes!””

“Let’s talk about some of the ways we sorted,” I continue.  “Remind me how we sorted our shapes.” 

I call on a student to remind us, “Color.”  Then another student is chosen to say, “Shape.”  Again, a student tells us, “Size.”

“How did we know the sorting rule for each sort?  Did your teacher tell you?” I continue.  “No!  We figured it out!” students respond.

“How does that feel?” I ask.  Some students say, “Good,” but I wait until students say something like, “I felt like the teacher!” or someone says, “I feel really smart!”  (That was the best response, I think!)