To introduce our new topic, I asked the kids to write the following math problem on their desk (using dry erase markers):
3 + 3 x 4 + 2 x 3 + 3
Most students solved from left to right getting an answer of 81. Other students are in UIL Number sense and had a better idea. They grouped the multiplication problems together and got an answer of 24. However, when I added in the parenthesis in the correct position:
3 + (3 x 4) + 2 x (3 + 3)
We found that the answer was 27. This lead into my lesson objective:
We will understand the need for a standard order of operations by investigating the impact that changing the order has when performing a series of operations.
I explained to the kids that there is an agreed upon order of operations: parenthesis, exponents, multiply/divide, then add/subtract. Knowing that just telling them one time would have little to no effect on their long term memory, I employed a tactic I had seen on one of my favorite blogs, Runde's Room. The link will take you to the day she chose to teach the order of operations using the game of hopscotch!
I decided to try this myself! I planned to take the kids outside and make hopscotch boards using sidewalk chalk and then doing all kinds of equations.....but then the cold front came through.... 38 degrees may not be cold to many people, but to Texans, you would think it just snowed! So, instead, I made hopscotch boards on the floor of my classroom with masking tape.
Then we played some hopscotch calling out the order of operations as we proceeded. To make it more entertaining (for me especially), we kept increasing the speed at which we played the game!
After playing hopscotch, we recorded our new learning in our journal. I found another blog whose teacher used the hopscotch method in her classroom and then created the PEMDAS graphic organizer that we used in class today. The video with information is at: Order of Operations: PEMDAS
I discussed that they need many different ways to help them remember the Order of Operations. My kids told me that they would never forget hopscotch, but I explained that they needed something that would not allow them to mix up the order of the multiplication/division, and addition/subtraction. At this point, I mentioned the acronym PEMDAS. I also encouraged them to use a mnemonic device to remember the steps such as:
To complete the day, we worked with a page from Mailbox Magazine called "A Skeleton of My Former Self." This page allowed us to work with the order of operations while finding answers to interesting facts about the body!
We did not quite finish all of the facts today, so we will do that tomorrow.
Since there was new learning today and I wanted the kids to showcase their understanding the knowledge gained today, I assigned an Order Of Operations Math Concepts Poster. This poster was created by Jen Runde, the author of the blog Runde's Room (I have attached the link for any interested in purchasing).
It was a busy class, but fun!