Here was how our **conversation** in math class (MFM1P) went…..How many pieces make up this Star wars Lego ship? We started with that picture and had a great conversation around Lego.

Then I showed this one.

Does the pool/hot tub have more pieces/less pieces/ or the same? This turned into “boy” Lego vs. “girl” Lego. My personal opinion is its all great…. My 3 daughters are just as excited to play with Yoda as they are with Disney princesses. Girls in the class agreed that they didn’t need their own line of lego!!!

I moved our conversation a little forward with asking Which costs more? And which **should** cost more?

Anna — Friends should cost more because it’s a newer brand.

Joe — Star Wars costs more because it’s a popular brand.

Jacob — The friends cost more because there are more pieces.

Kristen — Friends should cost more because the pieces aren’t standard.

How does Lego price it’s kits? Jacob suggested that its by number of pieces and the class agreed that has something to do with it. I Let them struggle here and see if they can discover the price per piece.

Some students found number of pieces per dollar and some found price per piece.

We all came to the same conclusion. We discover that Lego friends has the lower price per piece($0.08 compared to $0.11). **Is this always true**?

Let’s see! We go through a number of different Star Wars Lego sets finding the unit rates.

We notice that they are not all the same so we find the average rate.

### Get the whole slide show

We then go through Disney and Lego Friends sets and calculate the rates.

We saw that on average the Friends and Disney sets were $0.16 /piece compared to Star Wars’ $0.13/piece. Minds Blown!! We also graphed each on the same axis.

We then used our work to determine what each of these sets will cost?

**The class conclusion**: Lego sets are pricing their Lego Friends and Disney sets **higher** than Star Wars sets! Girl vs. Boy conversations came back up and I threw this set out at them……and they were **outraged** by the price!!!!!

I should let you know in my small class of 15 students……**12 of them** are girls!!!

Resources:

### Get the whole slide show (PDF) or Keynote

### Get the Desmos page

Update –Add ons — From Matt “Lego Activist” Vaudrey

@MrOrr_geek This was the image I sought yesterday. http://t.co/SzY8xmmWgq #feminism @LEGO_Group pic.twitter.com/CzFGpq3wBj

— Matt Vaudrey (@MrVaudrey) February 25, 2015