Our black lab Mandy is 3.5 years old, weighs a ton, and her breath used to smell like death. Until we started giving her one *Greenies* a day. My husband orders them from Amazon, he also gets them for our neighbor’s small dog Bailey.

Although both boxes weigh the same 36 ounces, Bailey gets 130 treats in the Teenie size and Mandy gets only 24 in the Large size. This caught my attention which led to this task with my 8th graders who happen to be working with similar shapes. (Like I had planned this all along.)

*Greenies* are sold in various size packages. I’m interested in the 27-oz and 36-oz.

To launch the task, I hold up the 2 treats: 1 Large and 1 Teenie. I tell them that there are 24 Large ones in a 36-oz package, and I want them I guess how many Teenie ones are in a 36-oz package.

Then I give the students these:

- The photo of the 2 packages (so they know
*only*the highlighted information in the table above). - Each group of 3 students get two real treats: 1 Large and 1 Teenie.

In return, the students need to give me these:

- A 2-dimensional outline (with dimensions labeled) of what a Petite, a Regular, and a Jumbo may look like. For example, these are the actual outlines of the Large and Teenie. They may write down the thickness also.

- A completed table with the missing counts filled in.

Highlights of this task:

- Kids use some known information to construct new information. They use modeling to figure out what the other sizes may look like and how many of them would fit in a 27-oz or 36-oz package.
- It’s kinda messy and weird. While the kids can measure whatever lengths of a treat, how do these numbers translate into the
*mass*of each treat? - It’s good to work with solid objects instead of just flat polygons when learning similar shapes.
- The reveal (Act 3) of something like this is always a lot of fun. Not only the reveal in the count per package, but also how close their outline sketches are to the actual treats when I bring in the Petite, Regular, and Jumbo.
- How much does a 36-oz package cost?
- Is the Jumbo a shot in the dark? Would kids think to ask me for the size of the dogs? How does this help, if at all?

[02/03/15]

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