Monthly Archives: March 2011

Percent Increase and Decrease

Here’s a sample lesson on Percent Increase and Decrease designed for a 52-minute Pre-Algebra class.

1.  Start by watching the video on ‘Percent Increase’.  Make sure that students have the handout so that they don’t have to write down the application problem.
2.  Have students work on the two ‘Group Work’ problems on percent increase.
3.  Follow the same process for ‘Percent Decrease’.
4.  Have the students do the Percent Increase and Decrease ‘Matching Activity’.  You need to have the tiles cut apart for them already.  If there is not enough time to complete this in class (There usually isn’t), suggest that the students take the activity home.  If you wish, have the students bring the completed matches back to the next class for credit.



This Calculus Game Needs a Sweet Name… Any Suggestions?

I just finished this new Calculus game in anticipation of teaching a lesson on The First Fundamental Theorem of Calculus.  I’m looking to give it a good name.  Any suggestions?

Calculus Game.pdf
Download this file

Jing Video and notes to accompany my lesson:

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Download this file

Jing Video and notes for the Second Fundamental Theorem of Calculus:

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Download this file

Download this file

Solving a System of Equations with Two Unknowns

A Sample Lesson on Solving a System of Equations with Two Unknowns
Before you begin, you may want to print the summary sheet below for reference.  The sheet happens to have a major typo, but I think that it’s usually fun for the students to discover it themselves. I’ve been generous enough to correct the typo.
Start out by watching this introductory video about solving an application problem using the addition method.  I recommend printing out the handout of what is covered in the video so that you can take notes as you follow along.

Go to Wolfram|Alpha and make sure that you know how to enter systems of equations there so that you can check your answer using this wonderful tool whenever you are at a computer.  Or even on the go, if you have a smartphone.

This is a link to the solution for the problem shown in the video:

Next, watch this short video on solving systems of equations using the substitution method.


If you have time, which I hope you do, please print out the page below, cut apart, and match the each system of equations with its correct solution.
Finally, here is a link to a wonderful on-line Jeopardy-style game for one or two players, that covers how to solve Systems of Two Equations (and Inequalities) with two unknowns.

Could We Have an Open Dialogue About Race?

Let’s face it.  I’m Asian.  I could definitely play the race card, but I don’t.  Because I don’t want to.  I don’t think that it’s the right thing to do.  I want to believe that it is dedication, hard work, and passion for what I do that is what will get me to where I want to be in life.

Last semester, on the first day of class, there was a group of rowdy students in my class that would not be quiet even after I asked them to be quiet more than five times.  The principle that this is unacceptable behavior for the college classroom is the least of the issues.  Although, in the back of my mind, I could tell that this particular group of students did not respect me.

I talked to my supervisor about this group of students immediately after the first class.  I tried to brainstorm some ideas with her about why these students might be disruptive in the classroom and how to remedy the situation.  One of my suggestions was that it could be my age.  Despite having 8 years of teaching experience, I am still a relatively younger instructor.  So, I wanted to bring this this up as a possible issue.  The one issue that I did not to bring up was the fact that I thought that the students might not respect me because of my race.  I wanted to give my students the benefit of the doubt that the reason that they did not respect me was because of my race.  Remember, this was the first day of class.  I did not want to jump to conclusions.

My supervisor told me that the entire situation was my fault because of my poor classroom management skills.  I was told that regardless of age, there were no other instructors in the entire building having similar issues in the classroom.  My supervisor informed me that she would be assigning me a mentor to help me with classroom management skills.  It turns out that none of the things I would do would resonate with these students.  

One of the the first things that my mentor suggested that I do is assign students to specific seating.  I decided to rearrange the tables and chairs to try to separate some of the students in the group who were talking and disrespectful.  And all I got were complaints such as ‘Well, that’s not where I normally sit!’  Even though this was my mentor’s suggestion, in my supervisor’s eyes, it was still my fault that this strategy did not work in the classroom.

Then my mentor suggested that I try doing some activities with the students that might relate to them.  So, during Black History Month, I tried having the students complete ‘Black History Month’ activities as they related to math, including writing a paper about a famous Black mathematician.  And well, the complaints kept on coming.  In fact, one student even told me, “I’m not going to do your stupid assignment!”  It’s almost as if the students were offended at the fact that I was trying to reach out to them because then they would have no more reasons to disrespect me.

So, when the end of the semester came, it came as no surprise to me that almost all of the student comments eluded to the fact that the students thought I was a ‘racist’ and a ‘bigot’.  One of my former students, who happens to be a Black student, confirmed with me that he knew that the students thought that I was racist, and a small group of them were even planning some death threats against me.
According to my former student, the students walked into the classroom on the very first day of class already believing that they should not respect me because I’m a racist because of comments that they had heard from some of my other former students outside of class.  So, they were destined to make life miserable for me to get revenge on me for being a racist.

First, let me say this:  if you think someone is racist, and you haven’t confirmed it yourself, aren’t you almost worse than the racist in someway?  If you don’t confront the person, you’re just giving the person an opportunity to move on and be racist in another place.  You need to talk to the person about the way that the person is behaving and confront the racist behavior head on.  Maybe the person doesn’t even realize that he or she is exhibiting behavior that you might perceive as racist.

Second, I have been a victim of racism myself.  One time I applied for a summer job, and I brought my application into the store.  When I tried to hand the application to the owner, she told me to just leave it on the counter and someone else would pick it up later.  When I was out of sight, I heard her say to one of her employees to rip up my application and that I would never have a chance of working there.  Another time, I volunteered to be a greeter for a high school event.  One of the organizers of the events told me that I was not welcome to volunteer at the event because he did not want ‘an overweight Asian’ person to be the first person one of the high schoolers would see when walking in the doors.  Racism hurts.  But it doesn’t have to bring you down.  And you don’t have to exhibit racist behaviors in retaliation.

Third, if you are a supervisor, and you have an instructor who comes to you with a complaint that the students in the classroom don’t respect the instructor, I believe that you have a duty to try to figure out why this might be.  If a student complains that an instructor doesn’t respect him or her, the supervisor is likely to do a classroom visit to try to validate the student’s complaints.  The same thing should occur if an instructor files the complaint to the supervisor about the students, as in my case.  In this day and age, just because someone has the title of ‘instructor’, does not mean that the students will automatically respect the person in the classroom.

So, after all that has happened to me in the past semester, I am wondering if could we please have an open dialogue about race?

More Student Feedback.

I'm really happy to report that this is ALL of the student feedback from my Saturday class that recently ended:

"Although I did not understand a lot of the material, the instructor was very informative and acted as if he had he students in his best interest."

"Jon is a great instructor.  He really takes his time to explain the topics with out getting behimd schedule.  I wish more instructors were like him.  The course should be a week or two longer to fully grasp all of the concepts that are being taught."

Encouragement for Any Teachers Out There…

I know it can be tough out there!  I just finished two of the worst semesters I have ever had back-to-back.  The students constantly had attitude problems and my supervisors scolded me for telling the students that their attitude was unacceptable for the classroom.  Well, I just received the first good news I have gotten in a while:  My online students (at at different school, that is) seem to like me.  It’s comments like these that make teaching worthwhile.

If I could give one recommendation for future reference, it would be: “Nothing, I really enjoyed having this class with the instructor! He had so much to offer us. He answered questions promtly and interacted with us in the discussions more than any other instructor I have had. It was great taking this class with him”

The most beneficial part of this course was: “the Instructor and his knowledge and ability to communicate with the students and help them to be understand their issue”

Pi Day Exponent Activity

This year on Pi Day I was teaching exponents, so I created an activity surrounding many of the common errors that I see many students make when working with expressions involving exponents.  I have attached the file to this post, and I would hope that people would know what to do with it, but let me explain anyway:

1.  I printed and cut out about 10 copies of the activity (I wanted to have the students work in groups of no more than 3).  I also like to have 1-2 extra copies because it has become seemingly noticeable with my classes that there are some students who like to take the activities home with them.  Honestly, if a simple game like this gets them excited enough about math that they actually want to do play math again when they get home, I’m all for it.  By the way, it worked out best for me to place the cut out pieces in 10 separate envelopes.


2.  The activity is simple:  The students need to match the problems with the answers.  Some answers have more than one correct problem.  Some answers have no correct problems (there are two ‘whammies’).


By the way, if you notice, I created this in such a way that it could be used anytime of the year.  I hope you and your students enjoy it.


NOTE:  I noticed after the upload that you need to actually download the file for it to show up correctly.

I Use Matrices in Everyday Life, Do You?

I am teaching a Finite Math class this semester and the majority of students in the class are business majors.  I’m trying to make the class as relevant to them as possible, so I’ve been reading magazines such as INC, and Entrepreneur to try to get ideas for things that I can talk about in class.  Well, here is one problem I came up with for my lesson on multiplying matrices.  And by the way, I put a copy of the pie chart from the magazine on the Document Camera before even starting (I brought the magazine to class, actually).

According to INC Magazine (March 2011), 54% of workers describe their workplaces coffee as tolerable, 30% great, 10% terrible, and 6% other.  Use matrices to answer the following questions:

1.  If a company has 5040 employees, how many fall in each category?
2.  Within this company, there are 3000 people in sales and 2040 people in marketing, how many from each department fall in each category?
3.  Using the results from part 2, how many employees in marketing thought that the coffee was terrible?
4.  Use matrix multiplication to verify that the row totals in part 2 match your answer from part 1.

The Snooze Button is Now a Math Problem

Yesterday I came across this problem while planning a lesson on ratio and proportion:

"When I woke up this morning, I hit the snooze button and got 10 extra minutes to sleep.  Every time I hit the button, I get 10 extra minutes.  At this rate, if my alarm first goes off at 5:30 and I hit the snooze button 4 times before I actually get up, what time do I get up?"

After careful thinking, it turns out that I wasn't actually interested in this problem at all.  I was actually interested in asking questions such as:

Does it make since to get 10 extra minutes every time you hit the button, or would it make more sense for the number of minutes to be related to the number of times that the button is hit?

Personally, I would love an alarm clock that gives me 10 minutes on the first hit, 8 minutes on the second hit, 6.4 minutes on the third hit, etc.  Then I could use this situation to talk about the limit of the time approaching zero.