Email from Grace June 12, 2002-  Hi Don, How are you? I'm fine. You know what? I got a 500 in the SAT in the mathematics section! So I got a scholarship to the 2002 Young Scholars Program (for the month of July 2002!). I hope when I am in eighth grade, I will be able to get a total of 1400 points on the SAT. Thanks for all your help, Grace 

Grace, a 6th grader in Chicago has been working with Don via AIM in his Math By Mail/Email Program since August 28, 2001. Grace and her two brothers also came to Champaign for two hours on September 22, 2001 and again Dec. 2, 2001.


On Feb. 2, 2002 Don received this email from a mother in Idaho: Dear Don, I bought your books last year and have done some of the exercises with my son, Andrew, who turned seven in December. They are fantastic! He is very gifted in math and has finished most of our district's 6th grade math curriculum.  I go to school with him each morning and do his math with him so that he has an alternative to 2nd grade math (he skipped kindergarten).  Is there any chance we could come and do some math with you?  He loves to find patterns and analyze problems and work with other people in math.  What do you suggest?  I am groping around to try and find some exciting alternatives for him.Thank you. Barb

Barb brought Andrew to Champaign from Idaho to work with Don March 11-16, 2002 !! "We had a great time working with you." -Barb. 


On January 8, 2002 Jacqueline, an adult, started working with Don in his worksheet book, using email and AIM.


James , a 9 year old in Tasmania, has been working with Don via AIM in his Math By Mail/Email Program since June 14, 2001.


Emily, a local 7th grader, started coming to Don 9/14/00, came all during the '00-'01 school year, has come during the summer of '01 and is coming during the '01-'02 school year with her brother and sister! Before she came to Don, Emily had started working on infinite series in Ch. 1 of Don's worksheet book. She had figured that 1/2 + (1/2)2 + (1/2)3 + (1/2)4 + ... -> 1 and 1/3 + (1/3)2 + (1/3)3 + (1/3)4 + ... -> 1/2. She graphed the partial sums at home for the infinite series 1/4 + (1/4)2 + (1/4)3 + (1/4)4 + ... Emily realized that 1/3 = 5 1/3/16 and the partial sum  5/16 (1/4 + 1/16 = 5/16) can be written as 1/3 - (1/3)(1/16) = 5 1/3/16 - (1/3)(1/16) = 5/16.  Each partial sum then, can be written as 1/3 - (1/3)(1/4)n and as n->infinity, (1/4)n goes to 0, and 1/3 - (1/3)(1/4)n   goes to 1/3. So the infinite series 1/4 + (1/4)2 + (1/4)3 + (1/4)4 + ... goes to 1/3. Emily saw the pattern of the other infinite series and this one, and generalized that the infinite series 1/n + (1/n)2 + (1/n)3 + (1/n)4 + ... goes to 1/(n-1).

Note: Emily and her Mom tore out the perforated, 3-hole punched pages in Don's worksheet book and put them in a 3-ring notebook. She is putting her work between the book pages and using the book pages as well.

See Emily's fine work on the snowflake curve and radicals, fractional exponents and logs. Emily was also accepted into UNI high school for the '01-'02 school year. Congratulations Emily! Emily and her brother and sister have come through the summer of '02 and are continuing into the '02-'03 school year. And Emily has been getting an A in math. What a pleasure they all are!


Natalie, a 7 year old, came from California for 5 days during the summer of 2000 and continued in Don's Math By Mail/Email program during the school year. The following is an excerpt form Natalie's letter to Don sent after she got back home to California (the typing takes away from her writing, drawings and math problems in the margins, however):

"Dear Donald Cohen, What I liked about your class most is your creativity. I had lots of fun because it was hard. (Are there any tornados?) I think kids in my old school would be amazed at what you do. I had a fabulous time with you. I hope every thing is going well. Are you having a good time? I hope you are !! Your student, Natalie" See Natalie's summer 2000 work here.

Natalie returned in August, 2001 to work with Don again!


Ashley, age 7, came to Champaign from MO to study with Don in August 2001.
See Toshio and Reiko's work when they were here for 6 days to study with Don, in the summer of 2001!
Natalie M. came to work with Don during a trip to St. Louis, in the summer of 2001. Also see her sister Wendy below.

Ryan, an 8th grade homeschooler, came from western IL, one day a week during the 2000-2001 school year.


Students who came to study with Don before the summer of 2000:

Katie C., came for 5 days during the summers of 1996 and 1999. Click here to see what KatieC did with Don in 1999


Jonathan, at ages 7 and 8, came from Connecticut for a week in the summers of  '89 and '90. His work is in Don's worksheet book and he is in both of Don's videotapes. Jonathan is now at Cornell, majoring in Physics. From Jonathan's Mom and Dad  in 1999:

"..We really want to thank you for your help in getting Jonathan started on a successful path in mathematics. As you can see [8 pages of his awards and records in HS] it has led to an exciting future career. He thinks that he might be interested in proving or disproving "string theory", but is open minded and wants to learn about all branches of physics when he starts out at Cornell. Your enthusiasm for math has set such a shining example for Jonathan and our whole family as you have pursued a life long love of mathematics and learning. We greatly appreciate your interest in Jonathan and your help over the years".


Grant K., starting at age 11, worked with Don in his Math By Mail program for two years and came from Oklahoma twice during the summer between. Grant is now in medical school.
Wendy, at age 12, came from Minnesota for 4 days during one summer, after earlier having worked with Don in his Math By Mail program for about 8 months at age 5. This was no surprise since Don had Wendy's Mom as a 7th grade student! Wendy is Natalie M's sister mentioned above.
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