About Don's teaching

September 2, 2012After the Summer of '12, Jackie working with Don, he received an email from Jackie's Mom:
"I have been passing your name around like candy. I am so delighted with the work you've done with Jackie. :)[Jackie is continuing with Don in the Fall].
:

2 January 2007 Don received an order for his 2-disc CD-ROM set from the begabtenakademie for gifted students ages 5-15, in Germany! Don sent this order with a copy of some pages from the German translation of his book "Calculus By and For Young People (ages 7, yes 7 and up)". This is exciting..we'll see what happens from here! 

From Bernd, the teacher in Germany, a month later: 

".. I've only started with the infinite series 1/2 + 1/4, ... with 3 groups: a group of 5-year-olds (8 Pupils) , a group of second graders (7-8 years; 13 pupils) and a mixed math group form grades 1 - 4 (12 pupils).

I called the lessons "Chocolate maths" because I like to use everyday things and in this case I bought some quadrilateral bars of chocolate of the brand "Ritter" which are 4x4 shaped.

Fractions are taught in grade 6 in Germany. Everything was really quite new for the children. Time by time I'm going to try your other suggestions and ideas..." Don was very pleased that his materials are being used in other countries.

22 March 2007: Jamie, an 8th grader, solves the quadratic equation  x2 - x - 1 = 0 by iteration.
8 July 2007: Don saw Khaki for the first time in about 17 years, having worked with her and her 2 brothers for many years. Khaki has a son almost 4 yo and another child on the way. She will be teaching 6th grade math next year; Khaki has Don's worksheet book and plans to use it with her class!

                     

Above photo is from the back cover of Don's worksheet book: Don, with Khaki at age 17, used the computer program Derive  to "zoom in" on a curve to find the slope of the tangent at a point on the curve, leading to the derivative. She was preparing for her Fall calculus class (see ch. 14).


30 April 2007: Don asks his students: Make up a new problem like you just did! Most answer, "I can't make up a new problem". What's going on?
7 February 2007 Don was interviewed for a 1/2 hour radio program via telephone by Beatrice Ekoko,  for their RADIO FREE SCHOOL (see #28 Mathman Don Cohen). Beatrice recorded the interview at CFMU 93.3 FM in Hamilton, ON, Canada;  she edited the interview, added some music and work she did with children using Don's materials. This is an all volunteer show by, for and about Un-schoolers/Home Learners. The 31 min. program can be downloaded by clicking on this link:
  http://www.radio4all.net/pub/files/grassroots@hwcn.org/125-1-20070213-0214rfse28.mp3

The broadcast was originally on the Radio Free School 1/2 hour slot on Wednesdays, 12-12:30 E.S.T. at CFMU 93.3 FM on February 13-14, 2007 and the following stations (check for times at these stations):

CKDU 88.1 FM Halifax, Nova Scotia;

Free Radio Olympia 98.5 FM Olympia, Washington www.frolympia.org ;
KRBS-lp 107.1 FM in Oroville,
California www.radiobirdstreet.org ;
Radio Free Veronica, www.radioveronica.us/rfv.htm,
West Point, PA;
Free Radio
Asheville, 107.5 fm, North Carolina main.nc.us/iww/fra/ 
  WXOJ-LP 103.3 FM, Northampton, Massachusetts
 


Katy and Shelby graphed the cost of mailing a letter in oz. using a postal scale, and found a rule. Katy and Shelby graphed the cost of mailing a letter in oz. using a postal scale, and found a rule.The ceiling of x is written as and is defined as: if a and b are consecutive whole numbers, and b>a,  if a<x<b, the ceiling of x = b. If x=b, the ceiling of x = b. So the ceiling of 1.3 = 2 and the ceiling of 2 = 2.

 


 November 2005 After working with Don for a few weeks on infinite series, K.C., age 7 11/12, came up with this statement: "  It's the opposite, when the numbers on top of two fractions are the same, like 5/3 and 5/2, the fraction with the highest number on the bottom is the smallest". WOW! Nice job, K.C.


On 8 April 2005 Don led a monthly meeting of the UI Physics Education Research Seminar. A member of the Physics Dept., Dr. Inga Karliner, and mother of a former student of Don's, had invited him. Don has always had a lot of respect for people in physics because they need to know the mathematics as well as the physics!

They were a group of 6 graduate Physics students and 4 faculty members. After introductions Don had them share 6 cookies between 7 people as Brad (who just finished 2nd grade) did it - when he couldn't share them, he cut them in half, (a natural and easy thing to do)- and each person ended up with  1/2 + 1/4 + 0/8 + 1/16 + 1/32 + 0/64 + ... cookies (an infinite series!) See sample problems from ch. 2 in Don's books .

This starts with such a simple idea, gets into important mathematics (division, sharing, fractions, infinite series), and most young people can and should do it!

Don emphasized that there are always patterns in mathematics, (a bimal .110110110... (from the tops of the fractions), versus the decimal 0.857142... obtained by cutting the cookies into 10 pieces instead of 2, both = 6/7), visualization (actually cutting the cookies (3x5" cards), the important mathematics (infinite series), listening to ones students, and learning to learn. Don was also able to show things on his website- like filling in squares to get infinite series as in ch. 1 of his books, starting graphs to slopes in ch. 6, solving equations in ch. 8, and the java applet IES in Japan did with a problem from ch. 11- see http://www.ies.co.jp/math/java/comp/itoi/itoi.html . Don learned some things also; it was a very exciting meeting!

13 April 2005: Don received this email from Dr. Karliner:

Dear Don,

Many thanks for your visit. I know that you warned us that you never gave a talk exactly like this, but the people who came to it told me it was very interesting to them and they enjoyed it. Some of them will probably visit your program when their kids are a little older. The kids who come to your program are so fortunate, you are forever interested in seeing how their minds work.

Best regards and many thanks from us all,

Inga Karliner

on behalf of the Physics Education Research group at the Physics Department at UIUC

13 November 2004 A voice from the past! Don received a call from Betty in Houston, who wanted him to work with a group to begin The Madison Project ll. Bob Davis (now deceased) was the director of The Madison Project starting in the late 60's. He wrote mathematics materials, made films of classes using these materials, and conducted teacher workshops around the country, mostly supported by NSF. Don continues to use his ideas with his students today. Don worked with him for about 15 years in the Clayton Public Schools and at Webster College in St. Louis, and in NYC, before coming to Champaign, IL to work with Bob on PLATO, a computer-based education system. Don worked with some great teachers during those 15 years, such as Betty, Kathy, Gordon, Jerry and others whom Bob chose to work with him in The Madison Project.

The idea is to really make a change in the middle school mathematics programs nationally, by using Bob Davis' materials, as well as changing how the teaching is done. The objective is to make mathematics something students enjoy learning and will use later in their life.


18 September 2004 See Don's work on comparing the spirals for the Nautilus Shell, The Fibonacci numbers, and the Equal Tempered Chromatic Music Scale.
2 June 2004
"Hi Mr. Cohen,
How are you and Mrs. Cohen doing? I hope you are both well.. I have just finished my first year of graduate school in physics at the University of _. I am working with _.. to explore the physics of particles containing charm quarks (particularly D mesons) more thoroughly. Currently I am looking for irregularities in the detector's magnetic field and unusual properties of the detector's momentum resolution..

 I still fondly remember the summer work I did with you so long ago now. It is great that you are so busy teaching and encouraging more students in mathematics. My brother and parents join me in sending fond regards.  Best, Jonathan"

(Jonathan was the first student who came from afar to study Don's calculus program and, with his Mom, the student who started Don doing his Math by Mail program. Jonathan's Dad brought him from CT for a week, two summers in a row, when he was 7 and 8 yo. Don is thrilled that his students are smarter than he is and are doing so well. Some of Jonathan's work is in Don's books and he is in Don's two videotapes).


21 April 2004: ..'My warmest thanks to you for all the help you have so obviously given others over the years'.. - G.P., grandfather of 9 yo ready to start working in Don's worksheet book.
26 March 2004:
Don completed his week as facilitator of an online Young Scholar Colloquium March 22-26, for Davidson Institute for Talent Development. Don's topic was "Iteration to infinite sequences, in solving quadratic equations, and obtaining infinite continued fractions". His work with the 14 students was enjoyable, challenging and a memorable experience!

9 March 2004: Don received this email from Dana in FL: 'I do not know if you remember my son, but he worked through a few exercises in your book back in 2002.  To bring you up to date, he is now 7 years old and in the third grade.  ..He is currently finishing the 6th grade program on EPGY.  .. I also think that he has mastered how to get through the EPGY levels without always having explored certain topics in much depth.  I think at the elementary level that poses few problems, I am worried about next year when he starts pre-algebra, however...Right now he plows through math on his own, but I don't see the same spark from him.  Further, he tends to be a perfectionist so I thought exposure to you and your philosophy might help him worry less about right answers and enjoy the process again.  Any suggestion you have would be greatly appreciated'.

Also on 4 November 2003 Don received this email from Christina in Seattle: "Dear Don, I am enjoying your materials very much.  I am intrigued that some of your materials have been translated into Spanish.  This is wonderful.  I am teaching a group of bilingual (native Spanish AND English speakers) teachers a calculus "romp" at this week.  I would so much enjoy being able to tempt them with some materials in Spanish.   

Is there any chance you can e-mail me the materials which have been translated?   That would be so helpful. I would be happy to pay, of course, and give all the credit where it's due.

I will try to send you an account of the three-day workshop when I return!"


A teacher and owner of a Juku school in Japan, visited with Don for the month of September 2003!

She had studied Don's books in Japanese and wanted to meet Don, observe him teaching and study math with him. She worked  hard and asked great questions, for the teaching of mathematics in Japan (as well as in the USA!), is much different than what Don is doing.

(She brought some origami paper and book for Don's students; and coincidently, see the origami story from the Christian Science Monitor ). She has asked Don not to show his write-up of what they worked on during the month of September. He will honor her wishes.


Wed, 27 Aug 2003 Don received this email:
Dear Don,

I had the pleasure to visit your site and the work of the children with you. It is wonderful.

We in Iceland are developing math workbooks for students and want them to also see how easy it can be to learn these concepts, especially if you were the one helping out! I was wondering if it may interest you to come to Iceland and or help us otherwise, to review the materials we are developing and help us to improve them? Right now we are focusing on just the student workbooks. In the future, we will be making teacher guides and I can see how in both contexts you could be such a great help.

Would you consider this. I look forward to hearing from you.

Warm greetings,
Sunita

Sunita Gandhi, Ph. D -... Tune in to see what happens!



Johann, age 5
now, came from California to work with Don the week of August 25, 2003! Johann's Mom was born and raised in Iceland and was here when Don received the above email from Dr. Gandhi- what a coincidence !?
Good to see you Lori and Joe! Those of you who are in the Kansas City area, you have a unique math program there called MathHead Tutoring. It is owned by Lori Johnson Morse, tel.: 816.560.8098. Lori and her husband came to visit and participate in, Don's classes in Champaign, July 29-30th, 2003.
Lori has been using Don's worksheet book in her program with elementary and high school students for many years now. She says in an email of September 30, 2003 : "One thing I noticed about what Don does is he makes the students work hard, think harder.  I could see the good effects right away".

July 11, 2003 "Hi Don!
I'm doing fine. School ended about three weeks ago. I'm going into 8th grade. I am currently attending the U of C Young Scholars Program. We're learning geometry. Right now, I'm working on groups, subgroups, and polyominoes.

At home, I'm learning Advanced Algebra. I come across many problems that are related to the questions in your worksheet book so I use the book as a reference tool.

Bye, Grace" (about 2 years after Don started working with Grace!)


Received after Johann returned to CA: '..I am still in awe at how much Johann learned while visiting with you.  He seems to have grown a lot in his understanding of many different concepts.  I wasn't quite sure how much a little guy like him could absorb in such a short amount of time, but he continues to surprise me.  I myself learned a lot about patience from you and although not able to apply it all the time, I am trying.  Don, you are truly a great and unique teacher''- Johann's Mom
On 4 November 2003 Don received this email:

'Dear Don, Just a note to let you know how helpful I continue to find your book and workbook.  Watching you work with children in person has increased my understanding of how math can be approached in a different and more meaningful way.  The way you interact with kids is truly masterful.  Math is more than just memorizing ways of doing problems and you are living proof of the excitement and stimulation that lies ahead for those who are fortunate enough to have contact with you'. 'Barb M., who brought her son Andrew to Champaign from Idaho, to work with Don for a week.


From the parent of 2 of Don's students, August 2003

"Typical approach studies one simple concept at a time- boring- isolated, irrelevant.

Instead- have a more interesting, complicated problem, that uses these concepts in finding the answer. This leads the student through math concepts, seeing them in their natural context and usefulness. Also, when the problem is finally solved, the "Look what I can do!" feeling spurs further exploration of math." Don would add :
visualization
look for patterns
learn to learn
every student is different
teach one student at a time
teach arithmetic via important mathematics
have students make up problems
have a student do the same problem, different ways
guessing is important

Try sample problems from Don's books, by chapter!

New discoveries, new student work and Don's new pages: Don's materials are certainly for Homeschoolers!, Johann, a 4 year old in California, starts working with Don via Mom; Ian, a 4th grader, adds sine waves at right angles to make a bowtie (Lissajous figures); Jesse, a 4th grader, finds a pattern to change a mixed number to an improper fraction; Tessa, 6 years old, solves equations and subtracts using negative numbers; Geoffrey's work on polypowers with fractions!; Don paints in watercolor with.. , +++

Science to math activities

The non-trivial use of Calculators and Computers in Don's materials

The important mathematics  in Don's materials

The importance of guessing

Patterns in Mathematics

On Thinking About and Doing Mathematics

Trig for Young People

Puzzles, Games, & Hands-On Activities Don Uses With Students

Who was that Mathman?

After 45 years of teaching math & parenting..


To order Don's materials
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