The above is a copy of Don's watercolor painting of The Nautilus shell; it is Don's logo. The shell is beautiful,  its shape a mathematical curve, and can be obtained from Shell World, at seashellworld. Also see the equation for the shell ,  making a spiral , IES java applet making a Nautilus, Xah Lee's work on spirals (and other curves) and student work on the growth of the Nautilus (chapter 6), and comparing the Spirals of the Nautilus shell, the Fibonacci numbers, and the Equal Tempered Chromatic Music Scale .

ようこそ; WELCOME ! عَلَى الرُّحْبِ والسَّعَة ; 환영받는; ¡bienvenido a casa!; 迎; karibu!; aa'o bhagat karna; Willkommen; Aapka swagat hai; kumusta,..and all the world.

 Refreshing insights into the learning and doing of some important mathematics, by young people (while doing lots of arithmetic, using many hands-on materials, science to math activities, and the non-trivial use of calculators and computers)-- for children, as well as adults. Don assumes only that a student can count.

   Don's keys:

        visualization,

        look for patterns,

        learn to learn!

 

To order Don's books and CD's on his secure order form

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

The Math Program

Excellent math instruction for all ages, and all abilities - for 32 years!
Prepare your child for Fall classes this Summer! It's a great help.

Don Cohen  217.356.4761     Jerry Glynn 217.328.1640

Exciting news- all the time!

From Mr. Sasaki at Kodansha Ltd., a month after they published the Japanese translation of Don's book Calculus By and For Young People (ages 7, yes 7 and up) in 1998: "We can say that your method was accepted to Japanese people as a kind of new text in which they could learn and understand math much more than ever before".

27 June 2008 Mom and Dad with their 6 children, drove down from North of Chicago. Mom and 4 children, 3 girls and 1 boy, worked with Don for 2 hours, while Dad and their two youngest children went off to the park. Click here to see what they worked on.
17 June 2008 Don received this thank you note from Paul, who came to Don from 3rd grade through 12th grade:
Dear Mr. Cohen,
Thank you very much for the beautiful graduation card, the gift card to Pages For all Ages, and for attending graduation. Even more significantly, thank you for providing a strong foundation in mathematics and for helping me through subjects I found especially difficult. Your innovative approaches and teaching styles kept math interesting and fun, while the teaching methods in school made it dull and repetitive. This approach has been something that I can apply to different aspects of my life, by looking at a topic from a different angle, I am able to much more thoroughly comprehend the subject.
Once again, thank you so much for all you've done.
Sincerely, Paul
Thank you Paul, for your dedication to excellence and being a wonderful human being, and to Mom and Dad, for making it all possible! You all have helped make the last 10 years of my teaching very enjoyable.
16-21 June 2008 Nanako came from Japan again to work with Don!
22 May 2008 From Elizabeth in Rock Island, IL, after her 2 days observing, working with some students, and studying with Don: "Dear Don and Marilyn, Thank you both so much for your generous hospitality during my visit. I am so excited to get to work on the workbook and also to show my children what I have learned. I believe that children need to see their parents learning, too..". Elizabeth, it was wonderful that you could come to Champaign, leave your family behind, meet some of my parents and work with some of my students. You did very well, had some fine ideas that we share, and even figured out the area and perimeter of the snowflake curve, using infinite series- not an simple task! Elizabeth plans to return with her 6 yo daughter in August.
3 May 2008 Don & Marilyn were in Albany, NY to accept his 2008 Excellence in Education award- see the program and Don after his speech . Don wants to thank the Alumni Association of UAlbany, SUNY, his friends, students and parents of his students who wrote to support his nomination. Don realizes though, that this award is not as important as his work with individual students over the years-and for that he is most grateful. It has been a great ride!

While in Albany, he and Marilyn drove past Bethlehem Central Junior High School (now Middle School) where Don started his math-teaching career in 1954!

April 2008 Margaret, an 8th grader, asks a great question!
15 March 2008 Jonty and George are returning to work with Don from MN in August, like last summer!
Don's latest release: a two-disk CD ROM set,  "Calculus For Young People (2 CD set)", ISBN 9780977949311, containing all of Don’s materials -3 books, 2 videos, map, & poster, listed here: 

1. "Calculus By and For Young People (ages 7, yes 7 and up)”
2. "Calculus By and For Young People--Worksheets"
3. "A Map to Calculus"-- a 15" x 18" flowchart, overview
4. Video #1 "Infinite Series By and For 6 year-olds and up"
5. Video #2 "Iteration to Infinite Sequences with 6 to 11 year-olds"
6. "Changing Shapes With Matrices"
7. “On thinking About and Doing Mathematics”-11x14” poster  

The two-disk CD ROM set above, sells for $64.95  + $6  s&h- for PC and Mac users.  

Besides the two-disk CD set above,
Don will continue to sell these items on his order form:

"Calculus By and For Young People (ages 7, yes 7 and up)"    (CD-ROM); ISBN 9780977949304 __________________ $17.95
 "Calculus By and For Young People--Worksheets" (CD-ROM);
        ISBN 9780962167478 ________________________$29.95
 "A Map to Calculus"-- a 15" x 18" poster-flowchart;
        ISBN 9780962167485_________________________  $7.95
"Changing Shapes With Matrices" (paper);
        ISBN 9780962167430 _________________________$9.95

See what Rainbow Resource Center says about Don's materials.

1 January 2008 What a way to start the new year! Don spoke to Jonathan (now 26 years old) and his Mom and Dad who are in CT.  Jonathan, at age 7, started working in Don's book Calculus By and For Young People (ages 7, yes 7 and up), with his Mom acting as his secretary. She sent his work to Don. (This started Don on his Math By Mail/Email Program). That and the following summer, his Dad brought him to Champaign for a week to work with Don. Some of Jonathan's work is in Don's worksheet book and he is on his videotapes.

Jonathan has finished the course work for his PH.D. in High Energy Physics and is working on his dissertation, which he plans to finish next year!

Don is very pleased when his students do well!

What a wonderful year 2007 has been. If we could only have Peace, and no one should go hungry!

28 December 2007: Don and his wife Marilyn celebrated their 55th wedding anniversary today!

 Marilyn and Don Cohen are excited about their part-time work as Shaklee Distributors and users of many Shaklee “in harmony with nature” products-100% guaranteed -nutritional supplements including the new VITALIZER, Get Clean, Cinch inch-loss program, air purifier and more!- and they want to share these with you. Please take a look at their Shaklee website if you want to feel better, want a healthy home, a healthy planet, and bring in some extra money.
27 December 2007: Marie, one of Don's students for about 3 years (~1980 in HS), stopped in to talk. She lives in Baton Rouge, LA. She was in Champaign to help her brother get his house ready for sale and has applied to Wolfram Research Inc. for a job. What a nice surprise! 

One summer when Marie was Don's student, he asked her to help him teach youngsters at Mt. Olive Baptist Church in Champaign. She did a fine job. Don still hears from former students in that summer class. Marie has kept in touch as she went on to graduate UI (with her Mom!), a Math major & Physics minor. Then went to work for Delco in IN, She got an EE degree at NC A&T State U, then her MBA at Tulane in 2006 She worked for Dow Chemical in LA and the United Way and Motorola in Champaign, now at Caterpillar in Peoria.

In 2006 she was going to Tulane U in New Orleans, cramming for exams, when her Dad called to tell her Katrina was on the way and she should IMMEDIATELY leave and come home to Champaign. She made it out, but lost everything, including Don's painting he had given her. Don gave her a new painting this day and his 2-disc CD set.

27 December 2007: Kelly W.  needed to pass her Algebra 2 class with at least a 76 to get into a School of Nursing at Barnes Hospital in St. Louis. She came to work with Don for 2 hours December 22, especially on partial fractions. She called this day to thank Don and tell him she got an 80 on the online test and was accepted into the School of Nursing! What a nice way to end the year!!
19 December 2007: Tara T creates an infinite series that Don hadn't thought of before!
17 December 2007: Fábio from Brazil purchased Don's books. He asked Don to do an email interview which is in Portuguese on a blog for students of Physics.
11 December 2007: See Erin K's work on infinite series + ( during Summer after 3rd grade and Fall in 4th grade)- she did something Don had not expected, and it made him work also!
27 November 2007: Don received this email from Lori Johnson Morse: "Hi Don, how’s it going?  You wont believe this:  R.K. wants to bring his daughter to Kansas City [from Tennessee] for a week for the math program!  He wants to work 4-5 hours a day.  If we can get this all worked out she will be my first to travel from another state.

He linked to our site from yours.  THANK YOU!" 
Don is pleased to recommend Lori; she and her husband Joe came to Champaign to study with Don a couple of years ago and their math program has flourished since then! Go Lori!!
24 November 2007: Don's son Brian made a beautiful, wooden 3-D diorama for the story written by Don's granddaughter Tara, for her UNI HS geometry class, at age 15, entitled  A Quest For The Sacred Golden Pineapple, Pine Cone and Artichoke.  The diorama includes 1.) a figurine of The Old Mathman holding a golden pineapple, made by Tara, within a dome, 2.) a watercolor painting by Tara and Don of The Old Mathman's house in the woods, and 3). a shelf underneath with a copy of Tara's story.

19&20 October 2007: Rachael worked with Don during her high school years. As a junior in a western University she returned during the summer of 2007 and returned again in October to work on an assessment test she needs to take for college algebra . What a nice surprise! [She did well!!]

 19 July 2007: Don received this email  from a parent who had purchased his 2-disc CD set: "..I just wanted to say thank you again for inspiring me and helping me realize that kids can understand and do so much more with math than many people are willing to believe..". 
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).

13 June 2007: Lori's Mom called to tell Don that Lori got into UNI High School and would continue to work with Don in August when she returns to Champaign- Congratulations Lori!!

                 Don's secure order form  

22 March 2007: Jamie, an 8th grader, solves the quadratic equation  x2 - x - 1 = 0 by iteration.
18 March 2007: "Hi Don, I am a college Maths teacher in the United Kingdom and I am currently working on trying to develop the idea of linking the Maths curriculum to real life examples where-ever possible. I have been looking at your website - example materials on the web, it looks great and was wondering whether it would be possible for me to purchase your 2 disc set about calculus for young people even though I am in England".- K.W., UK  Of course, and she did!
3 March 2007: Geometric Sequences and the 88 Keys on a Piano by Don
26 February 2007: An exciting day! John Melby, Emeritus Professor of Music at UI, who had moved to Mass. with his wife Jane Thompson a few years ago, dropped by to see Don and Marilyn. He came back for the premier of his computer composition at The Krannert Center, UI.

Don had his daughter Kirsten from 4 years old, maybe through 10th grade at UNI high. She just graduated with an M.A. from Munich U. in Germany. She is fluent in German and Italian, speaks some Thai, and will be studying Chinese soon.

Don had his son Charles from 5th-9th grade, also a UNI graduate. Charles received an A.B. in Physics from Princeton (Magna cum Laude) in 2006, just received an M.Sc. in Mathematics (with distinction) from Oxford in England, on a scholarship, and in 2007 is in a Ph.D. program in Physics at UC Berkeley. 

Would you say Dad was proud!!?? (and Don also!)

After Don congratulated Charles by email, on 27 March he wrote back: 

Hi, Mr. Cohen! It's great to hear from you. How have things been? It looks like you're still at it, teaching math to the next generation! That's fantastic, it's great that there's someone who is still working hard to show how fun math can be.

Incidentally, my dissertation was actually in... the theory of groups! Which, of course, I first encountered when you explained symmetries of the square to me. I hope you've had some other students who have taken a look at those same ideas, they're interesting ones and ones that kids are perfectly capable of handling if explained properly (as you do). Best, Charles

17 February 2007 Five views of  Don's Math Room - where it all happens!   
9 February 2007 Don received an order for his 2-disc CD ROM set from Moscow, Russia !!

7 February 2007 Don spoke to Loralee Johnson at "4 Your Mind" and told people during the interview that Loralee is selling Don's materials in Edmonton, Alberta, Canada and can be reached at 1-780-485-0969 or ljohnson@shaw.ca

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.
Check out  Lori's website for her "MathHead Tutoring Inc."

“..You wrote an amazing book.  Every week what my kids learn puts smiles on their faces.  It makes me smile, too.  You make people smile because they can understand math better.  It’s a gift and you share it with as many people as you can!  And I am having a blast following in your footsteps.  Much, much thanks! Lori”. KC, MO

See the internet links to Don's website and references to his books from around the world!

Homeschooling math by Don Cohen

                   “ ..Two roads diverged in a wood, and I - -
            I took the one less traveled by,
            And that has made all the difference.”

From The Road Not Taken  by Robert Frost. Don feels that what he has done is not the usual, and something that has touched many people, young and old, around the world, very positively, and has been very rewarding-  and that has made all the difference in his life!

 To get around on Don's site, choose from the menu below:

 

Don's Materials Will Teach You To:
Discover
Patterns
-New discoveries &

Patterns in Mathematics

Try sample problems from Don's worksheet book, by chapter!

Don's Materials
(all published and copyrighted by
Don Cohen-The Mathman)

Get Ready for Calculus
  1. Book: "Calculus By and For Young People (ages 7, yes 7 and up)" (CD-ROM)
  2. Worksheet book: "Calculus By and For Young People - Worksheets" (CD-ROM) & Table of Contents of books 1 & 2
  3. Videotape #1: "Infinite Series"
  4. Videotape #2: "Iteration"
  5. "A Map to Calculus"
  6. "Changing Shapes with Matrices"
     
  7. All of Don's materials are on a 2 disk CD set (see above)

 Science to math activities
The non-trivial use of Calculators and Computers in Don's materials
The important mathematics
The importance of guessing
Patterns in Mathematics

To order Don's materials

Visualize
Mathematics
Learn to
Learn -
Tessa at 5 works with Grandpa ! "When Grandma talks, everyone listens!"		  
What parents, teachers, kids, Martin Gardner, Morris Klein, W.W. Sawyer, the MAA, the ASCD, Kodansha, Mary Pride in her 'Big Book of Home Learning', the July/Aug. 2000 issue of The Home Education Magazine, The Math Forum.. say about Don's materials
On Thinking About and Doing Mathematics
Who was that Mathman?
'The Math Program'- Don and Jerry's great way of teaching math & loving it! (and what parents and students say about The Math Program)
How other sites use Don's ideas & his website
Don's Favorite Places on the WWW
Puzzles, Games, & Hands-On Activities Don Uses With Students
After 45 years of teaching math & parenting..
Links to this website- how many now ?
Don's materials are for grades K-12, ages 6-8 with adult help, up through pre-calculus students, adults, teachers, teachers of teachers, and parents!

Send email to Don Cohen concerning his 'Math by Mail/Email' with IM and video, coming to Champaign to work with him , ways he could improve his web site, or other issues. people have come in, peeked, glanced, shook, were curious, skeptical, impressed, excited, thought about what their children are doing in school or as homeschooled, tried a problem, solved a problem, emailed Don, called Don, ordered his material, .. since June 6, 1996. Notice, this site slipped past 200,000 visitors in early  2004- in less than 8 years!
                 Thank you for stopping, do try some problems before you go!

Don's web site was designed and started by one of his former students, Jennifer, while at MIT, and continued & maintained by Don, with some help from his grandson, Lian.