Day 14: Number Tricks

Today in Geometry I started with Mental Math where students compared two fractions. It is homecoming this week so everything was pretty crazy. We watched Dan’s Magic Octagon and took a few notes on rotations/reflections. After we made Hexaflexagons, which is where all chaos broke loose. I did not prep students well enough and we ran out of time, this was a bummer but I can pick up the pieces tomorrow.

In Algebra I had one of the best days of my teaching career. The lesson had awesome scaffolding and I felt like students took a lot of way from the day. I wrote about Jinx Math earlier this year and today built of those ideas.

I opened up with this:


I asked students to make a claim on what the number will always be, in this case it will always come out to 7. But mathematicians can be lazy so lets go ahead and write an expression that will do all these steps.


We walked through the first one together.


Let’s try another; make a claim on this one too.


After a few times through we translated this number trick to math as well. Students worked through this one on their own.

photo 1 (2)


“now we could do this again for the next 20 minutes but let’s mix things up”

Write the steps to this number trick.
Write the steps to this number trick.

They did an awesome job here! Later in the day I started asking students to name the number tricks, this was a lot of fun.

Check your steps.
Check your steps.

Time for the big one.


I was a little worried about how students would take this…

photo 4 (2)

photo 3 (2)
Trying to pull a fast one.

photo 2 (3)

I should never doubt student ability. They were lovin’ this.


I followed this up by working with 1 and 2 step equations – smoooooooth transition into this.


Credit for this goes out to Dan.

What a day!


One thought on “Day 14: Number Tricks

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s