Well, I bombed a lesson in geometry on geometric mean today. I went way too fast through the different similar triangles, tomorrow is a new day and another try at it. It is my first time through geometry so I am not as prepared in how to explain certain concepts. Whereas this is my third year through this portion of the algebra curriculum.

Anyways… I wanted to share one of my favorite openers (of all time).

Last year I asked them which calculator is correct. This year I didn’t say anything and let them ask the questions.

We are working on exponents and there have been some good discussions over order of operations since T.I. calculators say -3² = -9 and iPhones say -3² = 9. A good extension on this opener is to ask what solution each calculator would spit out for another expression.

*I don’t remember where this image came from… if you have seen it before let me know and will give out some credit.

### Like this:

Like Loading...

*Related*

Alyssa“tomorrow is a new day and another try at it” – Thank you for this attitude! So often, we can get caught up in not being perfect everyday, and really teaching is about trial and error and learning from it! What better way to teach the students about life in general 🙂

LikeLiked by 1 person