Posted on October 13, 2012


While I was off having a panic attack about how much grading I haven’t done, I missed a bunch of stuff. When I read the multi-day backlog, a call was put out to come up with 3act activities for the upper level maths classes. I posted about an activity I did for the probability unit of AP Statistics (Red Stripes blue stripes) that I stole from a book but I don’t have intact anymore (you know, one of those books that the pages are perforated so you can rip them out to scan…but I throw out the “shell”, which means I throw out the name, ISBN, anything identifiable…which means I’d probably be good at hiding a body or destroying evidence…but it also means I can’t cite it, which makes me not very happy.)


I don’t really think the upper maths are really that adaptable for 3act activities, not in their entirety. I do think 3acts are AWESOME for roping the students in enough to try stuff.

Especially probability, which has a horribly unjustified reputation of being difficult.

My brainstorm of the videos or pictures to set up the 3act for this activity…so naturally it has no organization or order:

I have no high-enough-quality camera equipment to do any of these.

I think the end of the Official Activity (“OA” so I don’t have to type it every time) is a pretty good setup to persuade the kiddos that they really really should be interested in this.

The OA starts small and ends big. The big activity will prove to be too difficult to do without a smaller, on-paper or on-whiteboard practice on a smaller scale.

Act 1:

You have just purchased a year’s worth of socks: 40 red and 20 blue. You throw them into the laundry before you wear them. They make it to the dryer. But then the power goes out, you wake up late…and you’re late for work and in a huge rush, and you run down to the dryer to grab socks for the day. Your clothes have red in it, and you really want to simply reach in and grab a pair from the dryer. You grab, end up with three socks instead of two, and head to where you left your shoes to put them on. What is the probability of ending up with a pair of red socks out of those three you grabbed?

Then ask the “what else do you need to know?” Hopefully the kiddos figure out this might be easier with fewer socks.

Act 2:

something about sampling without replacement? or start the 4 red/2 blue process? or do the students get turned over to the OA paper version? or something totally not in my brain right now?

Act 3:

Whether OA is done or not…maybe a split screen of all the possible outcomes? or maybe this would go in Act 2? I think the payoff is Act 3 though…

Methinks this might end up being something more along the lines of Karim’s Mathalicious stuff than a 3act. Not sure.

Posted in: AP Statistics, School