You wrote: >>>"[The use of calculators in K-4 math] serves nothing and it is harmful for the child math well being." While MPG's postings are generally puerile and offensive, he can (and does) offer supporting scientific evidence when he suggests that something is, or is not, effective. Your postings have been neither puerile nor offensive--but you don't offer acceptable evidence to support your opinions, either.>>>
I have not seen anywhere you made a clear explanation on what a 4-function calculator can serve in K-4 math class. On the other hand, I and others posted very logical reasons that also relates to my concern of adding too much inappropiate load onto K-4 teachers and students in math class. That is my base of saying "serves nothing". Having students use calculator to perform 2,345,234 + 1,232,554 while they are still struggling with 23 + 35 is to confuse them. The teacher might in occasion "demonstrate" such thing to student, but should make them understand that they should first be able to do 235 + 765 = 1000 effectively before they should "use" calculator to do such lengthy calculation to get the "answer" in math work.
To repeat briefly, what I against is a "too easy to use 4-function calculator" in K-4 math class.
You said: >>I call your attention to your statement "But I insist that they don't use it for doing math." What in the world *are* they using it for? It's designed for use in doing math, and for nothing else! (New slogan for NCTM: Calculators don't solve problems--people solve problems!) Perhaps we're using the word "math" differently.>>
They use for different purposes not directly relate to their "math work". Mostly, they see that as a "toy" that they can explore by their own freely. Sometimes, they push around to prove that "calculator is right" because they believe in the math in their "brain" perfectly. While most other kids who "use" it for "math" believe in calculator more than they believe in their "brain". It is a major difference? I emphsize again, it is good this way because they separate it completely from the "math work" so when they "do math", they will not think "it is so hard, why not use calculator", so they can still get the necessary discipline. At the age of 8, my son ask for a scientific calculator, I gave one to him. He explored a lot with it. He would come to me and ask what those functions mean. I will always try patiently explain it to him with thing that I feel he might understand but "without expecting him to understand at all". If he could not understand, he himself will say, oh well, I will work hard on my math, one of this day I will understand it. Yes, he is lucky that he has me around. But what he can still only learn what he is ready to learn. About the lengthy calculation, yes, in his fourth grade, once he was given a science project that involved very complicated lengthy calculation, he asked me if he can use calculator, I told him yes and told him that he has a good judgement on when to use calculator. At that time he could already do all the mixed arithematic operations with fraction and decimal. I did not need to tell him too much, with simple rule from the beginning, he get to understand what he is ready to understand.
My point is, their progress in math is not influenced by the access to the calculator because, they accept it that math work is math work, ( similarly, "doing word problem" is doing word problem, not "doing English" ). I have no objection for student to use calculator in science class or other class. I against using 4-function calculator for "doing math" in math class.
At this point, I suggest two things, (1) if we want to introduce calculator and computer to kids, why not create a "computer lab" for the whole school that student can visit regularly with a scheduled class ( once or twice a week? ) and they can visit by their own in free time just as they visit the school library, with supervision. This will be much more structural and cost effective. (2) (this suggestion is a little wild but why not?) All math class starting 1st grade should be taught by a "math teacher". Advantage? (a) this individual specialize in math teaching and will not be an average K-4 teacher who might be a great teacher but with mathphobia; (b) there will be continuity in 1-4 kids' math development. ( I have a lot of students came to me saying that they have not been taught or been taught just very briefly "in the end of some semaster long ago" on many topic. They said, the teacher in next grade never bother to cover those missing pieces.
What the calculator for? to save time to do "lengthy calculation" which the user are able to do with long effort. I don't believe we should give such kind of problem to K-4 kids before they have solid knowledge on arithmatic, "in math class". If you want to teach students some concepts in word problem, one can always choose those that they can calculate.