# Mood-O-Meter

6 mouths x 5 pairs of eyes = 30 different moods.

A few weeks ago I volunteered to lead a make and do session for a staff team building “fun day.” Two nights before the event I started prototyping this “Mood-O-Meter” which actually presented an interesting mathematical problem: what combination of gear teeth and multiples of eye and mouth expressions will display all possible mood options?

For example if I had two 12 tooth gears it wouldn’t matter if I put four eye expressions on one and four mouth expressions on the other because only four expressions out of a possible of sixteen would ever display.

If I printed four expressions on one 12 tooth gear and three on the other this would be even worse as only one mood would be displayed. The other eleven options would always be out of sync.

I settled upon a 18 tooth and 15 tooth with six eye expressions and five mouth expressions respectively to produce 30 individual moods.

My colleagues at Texas Performing Arts cutting out gears to make their Mood-O-Meters. They may have lacked the exuberance of my elementary aged students but when they meshed their gears for the first time they were positively giddy.

### 5 responses to “Mood-O-Meter”

1. Very cool! How did you use it in your fun day? Did everyone get to make one for themselves?

• Oops, forgot to mention that. That’s the risk of posting so late at night. Yes about a dozen of my colleagues made their own and I added a photo above to prove it!

2. Pingback: Mood-O-Meter Math | New Gottland

3. You never mentioned this project at all. This is very clever, well done. This feels like something that is very “EAST-ible”, I am seeing cintra, v carving, million\$ to be made!!!

• Thanks Paul, I kind of forget about it.

I’m thinking of making it pocket sized and laser cut. Totally EAST-ible. I just don’t think I’m EAST-ible this year.