Teach 180: Students Lack of Sleep (Day 102)

Students are naturally more engaged when the topic is of interest to them.  Today's topic in AP Statistics was a review of confidence intervals for a population proportion and our data set was the number of hours of sleep my students got on the first night of school.  I had gathered data from my students on the first day of school using a google form.  I saved the sleep hours column as a .csv file and imported the data into Fathom for us to review.

Next we created a column called "Less_Than_8_Hours" and created the formula at the left to change the quantitative variable to a categorical variable.  If the variable Sleep was less than 8 hours, a "Y" was displayed.  Otherwise an "N" was displayed.  So, what is the point estimate for the proportion of the 47 students surveyed slept less than 8 hours?  And what is the confidence interval?  After we calculated it by hand, we used Fathom to confirm our results.  Our conclusion is that we are 95% confident that the interval from 0.6702 to 0.9042 contains the true proportion of students who slept less than 8 hours the night before school started.  It's crazy to think that students were lacking in sleep even before the school year started!

Teach 180: Teaching on Snow Day #4 (Day 101)

Although it is a snow day, we must keep moving ahead in AP Statistics.  Other schools in the south start their review on April 1.  Because our school year starts later and we typically have snow days, we are lucky to have review begin by April 20th.  Losing one hour of clas today means one less hour of review for the AP exam.  Due to our new bell schedule this year, my one AP Statistics class has missed 5 one-hour classes due to snow, delays and early releases.  I believe my other AP Statistics section has only missed one class.

To try to keep some momentum going, my AP Statistics students will be greeted with an email from me at some point today. (It's still before 9 AM and I am pretty sure they are still sleeping.)  In the email there is a link to one of two videos.  Period A will be learning the lesson that Period F did yesterday - determining sample size and confidence level for a given margin of error for a confidence interval for proportions.  And Period F will be learning about the t-distribution and constructing confidence intervals for a mean.  Luckily for me, I had these videos ready to go on my YouTube channel thanks to snow events in 2014 and 2015.

Happy Snow Day everyone!

Teach 180: You Know You are Winning When...(Day 100)

https://chehockey.files.wordpress.com/2014/06/winner2.jpg

At the beginning of the school year, you quickly identify those students who you think will struggle.  They often have weak backgrounds in a previous math class and have a low self-esteem relative to mathematics.  (At my school, the students often cite "Hot Pencils", a timed math facts activity, as a pivotal moment that changed their view of mathematics.)  Sometimes these students will even leave questions blank on a test or quiz rather than risk putting something down that they think is wrong and in their minds, makes them look stupid. 

At the beginning of the year, I identified a few students like this in my PreCalculus class.  Today, I knew I had reached some of them when two of these students, independent of each other, asked me, "Why did log(-4) on my calculator give me an error message?"  It was at the end of class and it was totally unsolicited.  It's a question I had planned to ask my class that day, but we ran short on time.  The bell had rung and these two students stayed after the bell to ask me their question.  The fact that they had the curiosity to ask that question and not dart like Pavlov's dog at the sound of the passing bell means that I have won.  It means that they, too, are now winning.