Storm Bay Posted February 9, 2008 Share Posted February 9, 2008 You know, back before calculators were allowed on exams? Is there any point to having kids learn to use them? Any point at all? Also, when did you start letting your dc use graphing calculators. I understand that they do have to learn to use them nowadays, but I'd like my kids to know how to do Algebra without calculators. I don't even remember if logarithms were for Algebra or Trig as my high school days were long ago and far away (other coast). Quote Link to comment Share on other sites More sharing options...
Jane in NC Posted February 9, 2008 Share Posted February 9, 2008 In fact, there is no escape from logarithms in a Calc II course or even in Precalc when students do radioactive decay or exponential growth problems. Using logarithms as a calculating tool seems to have gone by the wayside with calculators. Everyone has their own comfort zone with calculators. Our rule has been to use one (if one wants) on any sort of application problem. So when my 9th grader did Conceptual Physics, he could use a calculator. He was introduced to the graphing calculator in 8th grade. I had him solve systems of equations using algebra, but check his solutions using graphs on the graphing calculator. I figured this was a good introduction to features like the trace key. As a math instructor, it has peeved me to see students turn to the calculator for simple calculations (like 24 x 15). My goofball son prefers decimals to fractions, with all operations performed by hand. Drives me nuts sometimes, but at least he isn't using the darn calculator! Logarithms usually rear their head in an Algebra II course; depending on the curriculum, it might be precalculus. Jane Quote Link to comment Share on other sites More sharing options...
Jane in NC Posted February 9, 2008 Share Posted February 9, 2008 Radiation monitoring is performed on a logarithmic scale. So logarithms have their uses in medicine and power generation. Quote Link to comment Share on other sites More sharing options...
Gwen in VA Posted February 9, 2008 Share Posted February 9, 2008 I posted earlier today on how I make my kids do without calculators until algebra 1, so you folks are probably going to be VERY glad that I am not your mother, but -- I still make my kids do the rudimentary exercises with tables. My younger ds just met trig tables for the first time last week. I debated whether or not to have him do the exercises -- I mean, he has a calculator and he has used it all year! But I am SO glad we had him do the exercises! Reasons for introducing tables -- 1) He had problems reading the table! He had to ask me how to look up the tan 17degrees!!!!! I expected him to be able to figure it out on his own. He is now better at reading tables -- and I expect that skill to carry over into economics and other social sciences as well. 2) Really REALLY understanding how things work. He had already done several exercises that showed him that the sine and cosine functions are cyclical. He understood the unit circle......and I still had to explain to him over again how to extrapolate sines and cosines for angles greater than 90 or less than zero. If I had had him skip the exercise and merely use his calculator, he would not understand sine and cosine functions nearly so well! 3) Using the tables, if only for a week, breeds a healthy respect for the cumbersome process engineers and scientists had to deal with until quite recently. So have them learn to use and table -- and then at the end of a few days' worth of exercises, smile, drag out the calculator, and say that from now on you are allowing 21st century technology to help! Quote Link to comment Share on other sites More sharing options...
Jane in NC Posted February 9, 2008 Share Posted February 9, 2008 so you folks are probably going to be VERY glad that I am not your mother... Well, Gwen, my son uses old Dolciani texts which have tables in the back of the books. He has found that sometimes it is easier to use the tables than to hunt for a calculator. What I have not made him do, however, are the interpolation problems that I had to do back in high school. I viewed those calculations as a drag back then and would not subject him to them. But I agree that knowing how to read a table is a good skill. One problem that inevitably arises in trig when a student becomes heavily dependent on calculator usage is that the student doesn't think about a common sense, expected answer. So his calculator may be set in degrees, not radians, and his answer is nowhere near correct yet he doesn't realize this. I think that doing calculations away from a calculator will give students a more intuitive sense of what is going on. Jane Quote Link to comment Share on other sites More sharing options...
TRILLIUM Posted February 9, 2008 Share Posted February 9, 2008 Well I didn't plan on letting my dd use a calculator until Algebra 2. Then in geometry she had sines and cosines. I told here to look at the table in the back---but of course there wasn't one. Hey my chem teacher made us learn to use a slide rule. Quote Link to comment Share on other sites More sharing options...
Gwen in VA Posted February 9, 2008 Share Posted February 9, 2008 There were no tables in the back of your algebra 2 book!!!!! Times have changed! Our algebra 2 book is from 1992 and it still has tables (Dociani). My kids have told me that I need to keep our old math texts -- now I see why! ;) Quote Link to comment Share on other sites More sharing options...
WTMindy Posted February 10, 2008 Share Posted February 10, 2008 the calculator can do it for you. I would, however, teach logs and what the calculations mean. Quote Link to comment Share on other sites More sharing options...
Storm Bay Posted February 10, 2008 Author Share Posted February 10, 2008 Thanks for all this insight! Actually, I WANT her to learn to read the tables. We did EVERYTHING by hand when I was in high school. Calculators were new and very, very expensive. I didn't buy one until my post-secondary education when it was required. So, I may just buy a used old book to get that table. I would like her to learn to do extrapolations, but not to require it all the time. I LOVED math until the school system drove it out of me (long story I may have told on the old boards, and I won't bore you with it here!) Dd doesn't have a calculator yet, and I love the idea of having her solve the problem and then use the graphing calculator to check her work. That will allow her to learn to use the calculator for when she needs it, but still teach her to solve the problems the old-school way. I just didn't want to be the only parent who did that. I'll have to start looking for a used Dolciani if there are no tables in the text we buy. Quote Link to comment Share on other sites More sharing options...
Storm Bay Posted February 10, 2008 Author Share Posted February 10, 2008 What I have not made him do, however, are the interpolation problems that I had to do back in high school. I viewed those calculations as a drag back then and would not subject him to them. But I agree that knowing how to read a table is a good skill. One problem that inevitably arises in trig when a student becomes heavily dependent on calculator usage is that the student doesn't think about a common sense, expected answer. Jane I don't think I liked doing interpolations, either, but it's too foggy now! I want my dd to learn common sense, too. One of my biggest goals is to teach my children to THINK.:) Quote Link to comment Share on other sites More sharing options...
WTMindy Posted February 10, 2008 Share Posted February 10, 2008 would we make kids do something the long way without using technology available to them? When we wash the clothes we don't go back and scrub things by hand just because our grandmother did it that way and that is the only way to truly make sure that the clothes are clean. We use our technology to make our job easier. But, we also check to make sure it is doing the job. Did it get out the stain we had on the collar? You see the analogy. I find very little value in having kids do things the long way just because we did it that way. Do they need to know how to read a table? SURE! But do they need to know how to read a log table? NOPE! Do they need to think to make sure their answer makes sense? ABOSOLUTELY, whether they use a table or not. I have a degree in math and taught math at the high school level and I say let them use the calculators for this type of thing. :-) Amen. Quote Link to comment Share on other sites More sharing options...
Storm Bay Posted February 12, 2008 Author Share Posted February 12, 2008 As an avid mechanical dishwasher user I think this is a great question. First, all my kids will learn to do many things by hand just so they have the skill (washing dishes by hand because the dishwasher might break, or because not everything can go in the dishwasher.) Secondly, it has a great deal to do with thinking skills, IMO. My kids WILL learn to do these things on a calculator, especially interpolations. For that, I just want them to learn how to do it with the tables so that they have an idea of what the calculator is doing. I still benefit from taking a course in Assembler because I understand more of how software actually works. I freely admit to being old-fashioned/old school in many areas. My kids will eventually need to do a great deal on calculators, particularly my eldest if she continues with her desire to be a science major. But she won't be totally dependent on them. fwiw, I also plan to have my kids take a basic survival course in high school in order to graduate, etc. I just think it's good to know. Quote Link to comment Share on other sites More sharing options...
Susan in IL Posted February 14, 2008 Share Posted February 14, 2008 I didn't let my ds use a calculator until 1/2 through Alg. II (Foerster). He had to learn it the long way to know WHY he was pushing the buttons. I did show him how to use log and trig tables. He took pre-calc and AP calc at the local high school and when it came to tests where they were not allowed to use the calculators (prep for AP test), he never had any problems and could whiz through them while the other kids suffered. Ds 2 was given a TI-83 in 8th for alg. 1 in ps. I wouldn't let him use it since he got more wrong than right using the thing. He didn't know WHY he as pushing buttons or even how to check to see if the answer was right. They didn't have calculators when I was in school. And even when they came out, all they did was add, subtract, multiply and divide. We had slide rules and tables in the back of the books (we used Dolciani). Foerster's Alg & Trig book has log and trig tables in the back. One more thing -- The college that my ds attends only allows a TI-30 II scientific calculator for Pre-Calc, Calc, Gen. Chem I&I, Biology, Organic Chem I&II, and Calc based Physics. He hasn't taken BioChem or Biostats yet so he doesn't know what those will use. He left his TI-83 at home 2 years ago and hasn't picked it up since. Sorry, early calculator use is a pet peeve of mine. Quote Link to comment Share on other sites More sharing options...
Storm Bay Posted February 15, 2008 Author Share Posted February 15, 2008 I didn't let my ds use a calculator until 1/2 through Alg. II (Foerster). He had to learn it the long way to know WHY he was pushing the buttons. They didn't have calculators when I was in school. And even when they came out, all they did was add, subtract, multiply and divide. We had slide rules and tables in the back of the books (we used Dolciani). Foerster's Alg & Trig book has log and trig tables in the back. Sorry, early calculator use is a pet peeve of mine. I'm a mean mom with you, so I feel better. My dd is just finishing Agebra 1 and has never used a calculator in her math lessons. I'll keep Foerster's in mind as well as Dolciani when we get to trig and the tables. I used more than one Algebra program in high school as they changed when I was in Gr 10 (sophomore) then I moved to CA for the following year and it was different again. But we did it all without calculators. But someone did tell me that kids need to know how to use them and that it takes time to learn, so eventually we're going to have to buy one. All we have are cheap, simple calculators so far, and when the kids use them (rarely) it's not for their math lessons, but as a toy. Quote Link to comment Share on other sites More sharing options...
ereks mom Posted February 15, 2008 Share Posted February 15, 2008 I still make my kids do the rudimentary exercises with tables. Same here. "Why?", some may ask. For the same reasons that I insist that my dc be able to do addition, subtraction, multiplication, and division on paper instead of using a calculator. I want them to understand the process involved in arriving at the answer, not just how to punch calculator buttons. Quote Link to comment Share on other sites More sharing options...
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