Saturday, April 9, 2016

Pentominoes! Geometry fun in third


My favorite math center regarding geometry? PENTOMINOES!!!!! Pentominoes are the best for geo-spatial thinking, perimeter, area, and challenging early finisher work. 

My school gets Pentominoes in all their sturdy, foam glory. However, if your school either will not purchase the resource, you can also get a paper version and the kids can cut them out. Here is one offered by Scholastic I found online. Just type in "paper pentominoes" :-)

I do a lesson to introduce Pentominoes to my students to gauge interest. After the lesson, the Pentominoes are a center all year for the kids. My kids are seriously obsessed with these things. We do quiet time for ten minutes every day after lunch, and usually kids draw, color, relax, etc. Once Pentominoes are introduced, half my class chooses to work on these challenging math manipulatives! They offer a fantastic level of engagement and interest with students.

I start off writing "domino" on the board. I ask the class what this is, and every hand immediately pops up! I ask one of the students to come up and draw a domino for the class. I ask them what does a domino look like? Specifically, I am looking for the answer that a domino is two squares side by side. 

Next, write "omino" above the word "domino" and the picture. Explain that "omino" means a square, and draw one on the board. Then, draw three squares next to each other, and ask kids what word they predict will mean three squares next to one another. Usually about half my class can automatically figure out that it is "triomino," using their background knowledge from "triceratops," "triplets," etc.

Next, I give my students a white piece of computer paper, and a handful of colored tiles. I ask them to make a triomino, which requires three squares each. I remind them the guidelines that the tiles MUST be touching on at least one side. Together we figure out all the different shapes that can be made. 

Here's a key:
1 square = onimo = 1 shape 
2 squares = domino = 1 shape   
3 squares = trionimo = 2 shapes
4 squares = tetronimo = 5 shapes
5 squares = pentonimo = 12 shapes

Many kids will want to take the pentomino shape, rotate it, and call it a brand-new shape. I like to tell them, “An ostrich can lie on the floor or stand up. An ostrich is an ostrich!” You can see in the picture that even though a shape is rotated or reflected, it’s still the same shape!

Different shape? NOPE! Just rotated.

There are a total of 12 pentomino shapes that can be made. I hand out square tiles, and tell the kids to figure out the different shapes (I don’t tell them that the total amount is 12!). I also hand out a blank piece of paper for them to record each on. Then on the document camera, students come up and build their shape. Together, the class figures out if it is or is not a pentomino shape. Is it rotated? Is it reflected? Are all sides touching?

This lesson results in a lot of "OHHHH" and "AHA" moments. Aren't those lightbulb moments the best when teaching? 

There are lots of packets available on Teachers Pay Teachers, but your math resource coach or professional development library may already have pentomino resources in them (that's where I got mine!).