M&M / Skittles Laboratory: z-interval for a mean & z-test of a mean

(easily adaptable to t-procedures)

Lab Sheet -- what I give the kids. it has a front & a back side.

Data Spreadsheet - to check answers etc.. Really neat if you can project it on board.

Template - an ALL-PURPOSE template for Confidence Intervals & Significance Tests!

Conclusions -- what their writeup might look like

Pictures of Scholars doing this lab: Picture1 Picture2 Picture3

Tips/hints for lab

-- on lab days, my kids are randomly assigned to a team. Every group of 4 seats has a name: Alpha, Bravo, Charlie, etc. Kids pick a slip of paper from a pile on the way in and go sit at the table with the name they picked. First thing: Tell everyone on your team your name. Second thing: say something nice about everyone on your team. OK, now start the lab!

-- have at least 2 (preferably 4) balances for the kids to weigh things.

-- remind them repeatedly that we have TWO DISTINCT tasks: 1) write a CI for the mean number of items in a bag and 2) do a sig test on the mfg's claimed mean net weight.

-- give each group paper plate(s), napkins, cups, etc.;  see above pictures of kids doing lab (more pix avail if wanted)

-- remind them that for the weight test we care about NET weights (candy only!) not gross weights.

-- give each team 1 bag of MM, 1 bag of skittles. But if you want to cut things down (perfectly OK) , just do ONE candy.

--esp. for beginning statisticians: do ALL work on the Template sheet. Get used to a good format for writing CI's and Sig Tests.

-- put a copy of the data tally sheet on the overhead projector; have teams come up & fill in data as they get it.

-- If you've got Excel, load their numbers into the Data Spreadsheet in the appropriate places for a quick automatic check on their work. Even better if you can project this spreadsheet on the board for all the cherubs to see.

-- take pictures. Save for next year. Print a few & post in classroom. Use for recruiting next year.

-- I've got an MM PROPORTIONS lab that I'll be posting soon.

Please contact me with any other q's. -- randy.bailey@district196.org