Size Sorting on the Big Screen

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SWBAT sort objects by size.

Big Idea

This Promethean board activity eases students into the challenge of sorting objects by size, getting progressively more challenging as the activities continu

Attention Grabber/Introductions

3 minutes

There’s something about a giant, projected, colorful Promethean activity that doesn’t need too much introduction.  I’m not saying that I don’t do an introduction when I used the Promethean board, but I am saying that as well as I tend to hold their attention most of the time, they are really much more interested in the fun, giant, multimedia activity that is just waiting in its “larger-than life” way.  (Needless to say, I have my computer hooked up and my slideshow ready to go as the students enter the classroom.)

As we walk in from lunch recess, I tell the students, “Yep—girls and boys!  It’s a ‘big screen’ day!  We will be sorting--by size--on the Promethean board!  So what are we doing?”

The kids yell, but I try to encourage raising hands, (which does get kind of pointless when the kiddos are so revved up, but I try to be consistent), “Sorting!”

I ask, “Sorting?  How are we sorting?”

Then I choose a kid who isn’t raising a hand, (because I like to be sure that they’re all learning), and that student says, “Sorting by size!”

“Hmm…” I expand, trying to reiterate our math vocabulary, “What is that big math word that refers to the way we choose to sort?” 

Awkward silence.  So I hint, ever so slyly… “Att…

One of the little “sponge” kids who seem to just soak up every ounce of learning raises a hand—because of course, the sponge kids have soaked up the rules!

I gesture to the perfectly raised hand, and the sponge-like student responds, “Attribute!”

Exactly!  Let’s all say that. Attribute! We are sorting by the attribute of size!”

Guided Practice

20 minutes

Using the sorting by size flip charts from this website, (after skipping the colorful sorting by color, which I also recommend), I remind the students that we will all get a turn to sort an item.  Some of them actually bounce with enthusiasm!

For logistics, it is good to have a space in front of the board for students to stand, but also space along the edges of your circle time area so students can walk up to the board.  The people who mounted my Promethean board put all boards at a standard height, so I bought a little stool to help students reach the board.

I slide the first object into the big circle, saying, “Remember, as you slide stuff, to hold the pen without pushing the little gray button.”  (I hold up the stylus, showing the button that they should avoid.  Some kids will invariably push the little button, but this reminder helps about 70% of kiddos.  (When kids push the button, usually the other students will remind them, “Don’t push the button!,” and all you need to do is turn the stylus so that when they put it back on the screen, the little button won’t be pressed.

Students take turns passing the stylus and sorting the shapes into the large or the small circle.  As students take a turn, I say, “Pass the pen to a girl!” or “Pass the pen to a boy!”  The students know that they only raise their hand until they have a turn at the Promethean board.

To help ensure students have success sorting in front of their classmates, I choose a student who seems to really understand sorting well.  As the activity progresses, fewer shapes remain to be sorted, so it becomes easier for students to sort correctly.  Allowing some students to take their turn later in the activity allows for more modeling and it also reduces options for sorting, so it becomes easier for students to sort correctly.

The second sorting by size activity includes shapes of different sizes and different colors.  We repeat the process, with every student taking a turn at the “big screen” to sort an object.  Check out the video for this lesson to see what the students did and how I let them struggle for a second before calling on a little guy to save the day—having a student solve their dilemma is far more empowering than me personally swooping in with an answer!


Independent Practice

15 minutes

To have tangible “proof” that we are gaining understanding of sorting by size, I send the students to do a quick sorting activity as independent practice.  I use the same mat I’ve used on a couple other sorting activities.  It’s simple, but it works! 

I included triangles & hexagons in two sizes for the students to sort.  I chose triangles and hexagons so I can get students talking about these two “tricky” shapes.  I circulate through the room, but I will swoop in ever so carefully to ask the kids who were confused with “triangle” to tell me what they were sorting to the big side, just so I can quickly check if they’re making any progress with their shape vocabulary.  I do the same to check hexagons.  Of course, I'm mainly looking for sorting by size, but I may as well make the most of the activity!

As students finish, I encourage them to color their sorting mats.  This takes a little bit of time while other students finish their activities, but more importantly, it provides an opportunity for students to demonstrate their understanding.  One little guy tells me, "I can use lots of colors because it doesn't matter what color they are!  What's important is the size!"

The completed activity can also be used as a formative assessment.


5 minutes

As students finish their size sorting, I ask the students about our activity. 

“So friends,” I say, “How did we sort today?”

“By size!” they respond.

I ask—but I know the answer before any words leave my mouth—“What was your favorite part of sorting today?” and I call on students.  They invariably say, “Sorting on the big screen!” but it’s fun to hear their excitement about sorting.  Every so often, someone will say something like, “I liked helping [student name] remember to hold the pen the right way,” or, “I liked when [student name] saved the day and moved the big rectangle into the big side on the tricky sort!” which I will restate, agree with, or otherwise highlight so that our lesson closing doesn’t just recap lesson objectives, but it also builds classroom community.