OoO: Four 4’s

Back in late July, the call went out to the mathtwitterblogosphere to share first day/week activities. Since late July isn’t even the halfway point of my summer vacation, I resisted the urge to blog at that time. Instead, I lurked and reflected. A month later I received an email from a colleague asking for some first day ideas. In this post I’ll share one of those ideas.

It’s common for middle/high school teachers to begin the year by reviewing order of operations. The thought here is that a mastery of OoO within arithmetic is necessary for student success in algebra. I’m not convinced (see Timon’s post).

On Day 1, I’d often overhear a student say “What a geek! He’s got a math clock.”

Taking advantage of this, I’d ask students to find expressions for the numbers 1 to 12 using four 4’s and mathematical symbols (+, −, ×, ÷, brackets, decimal point). If I were to start the year with OoO, the the four 4’s puzzle would be an improvement on the BEDMAS worksheet. Each student can contribute something and gain confidence by solving the problem. This is important on Day 1 (and Day 93). Multiple solutions are shared and appreciated.

By giving students a target number, rather than an expression, the need for a rule to clarify ambiguity arises. It becomes more than a mnemonic to memorize. For example, students may present the first expression below as a solution to target numbers of 3 or 9:

(I’m not sure if these add anything to this activity, but if you want these cards, here they are: Four 4’s)

Last year, I wrote

I’m just not able to lecture students for 75 minutes about consequences of unexcused absences, procedures for handing in homework, and lists of food & drink items that are acceptable to have in the classroom. Imagine sitting through this four times on Day 1. Welcome back!

On a personal note, I hope that Gwyneth is as excited about the first day of Grade 12 as she was about the first day of Grade 2 (and Kindergarten). I hope that she’s doing math on Day 1 (and Day 93).

Gwyneth Day 1 of Grade 2
Gwyneth Day 1 of Kindergarten