Looking for a fast math lesson to extend learning and use critical thinking? You’ve come to the right place. Because I only get to see my gifted students for 40 minutes a day; and that includes walking in the door, settling down, packing up, and exiting; I must make my lessons quick. Recently, I built onto a lesson that I loved in the past: “Box O’ Blocks.”
Prep: Take those classic, little-kid, wooden blocks and stick 3-digit numbers on the sides. Put them in a box. You are ready to go!
If you don’t have access to blocks, you could draw, color and cut out different shapes on card stock or index cards. Basically, simulate the classic building blocks, but 2 dimensional. Have the kids make them for ownership of the game. (Instead of “Box O’ Blocks,” it could be “Construction Cards.”) This would be easier to store, lend to other classrooms, as well as quieter;)
I began with a game so simple my 3rd graders could learn and play without use of any writing materials. Pull three blocks out of the box. Round them to the nearest hundred. Add them together. Closest to a 1000 wins.
Our first round had two teams get 700 and the third sum was 1300. At first they thought that thirteen hundred won. “Wait a minute,” I warned. “Are you sure?” Upon revisiting the numbers after I wrote them on the board, my students realized it was a tie!
After a few rounds of this, I introduced the idea of trading a block. “If you could trade a block to make your total closer to a 1000, which one would you eliminate?” They hadn’t seen all of the numbers but enough to make an educated guess. “If you have three blocks, and they are the numbers 513, 522, and 346, you might want to trade the largest. It puts you way over 1000. This would make room for a block closer to 200.”
Another fun variation that you could try; I didn’t, so I don’t know how well it would work, but it seems fun; is to let teams trade with each other.
Here’s some easy-to-use enrichment: Rather than round to the nearest hundred, have students round to the nearest ten. Or, you could do what I did in my original lesson; Don’t have them round at all. They will need paper, dry-erase boards, or iPads to write on for this.
What I did with my gifted students is I had them actually construct towers that they measured to use an additional 3-digit number for lowering or raising the sum of the original three blocks as necessary. Here’s how it worked. Pull three blocks from the Box O’ Blocks. Round to the nearest ten. Add the three numbers. Evaluate how close you are to 1000. The difference is what you want to make up. If you are over a 1000, you want to take away from your sum. If you’re shy of a 1000, add. Next, you get to build!
Students construct towers with their three blocks. They then use rulers or yardsticks to measure from the base of the structure to its highest point. Round to the nearest inch. Multiply that number by ten, and either add or take it away from your original sum. The trick is that the students can reconfigure the structure to be taller or shorter.
This lesson incorporates an idea I had several years ago: Action. I wrote a blog all about an elaborate lesson involving purchasing blocks, constructing castles, homes, structures and renting them to make back their initial investment (purchase price). It was fun, but long; Great week-long project.
The way that I assessed the success of each group/student and the lesson was through the use of Google Jamboard. I made a Jamboard with the instructions on the initial board, leaving plenty of blank space. This was pushed out through the Google classroom, “mak(ing) a copy for each student.” I modeled how to use the Jamboard to take pictures of the blocks, showing the numbers. Then I used the writing tools in Jamboard to write the rounded amounts of each block. I added them all together for a total that could be evaluated next to a thousand. We discovered that I was over one thousand, so I will want to subtract. Once we got the blocks to reach the perfect height, where the number of inches times ten would lessen my original number just right, I used Jamboard to take a final picture and show my last computations.
It is very easy to create a new board by pressing an arrow at the top of the screen. Then you start over. Pull three new blocks…
One group was 380 more than 1000. They were trying to make their tower 38 inches high, so that they could take 38X10 away from 1380. I told them to trade one of their blocks for another from our Box O’ Blocks. When they went to trade a teeny tiny one, I questioned them. “That block is only 300 (It was actually 296). The other two are both over 500. If you traded one of the blocks that was worth a lot, you might not need to construct as tall a structure.” They were interested in trading the tiny block because they were aiming for height, but was that the best strategy?
I summarized this story to close our class time. And, it was off to collect some more gifted students from a different grade to teach a different lesson.
The Captain of Class 