kalanamak Posted January 3, 2012 Share Posted January 3, 2012 I just cracked open SM 4B, and over half of it is decimals. How did we get there so quickly? Anyway, I'm hyperventilating a little. How did you introduce decimals? I like to do some hands on demos before cracking open the book. I've already read up on the Roman concept of decimation, which will certainly perk his ears. Quote Link to comment Share on other sites More sharing options...
.... Posted January 3, 2012 Share Posted January 3, 2012 :bigear: I'm right there with ya'! :nopity: The best thing that I can come up with is...money (coins are a fraction of a dollar). And that's where my incredible insight ends. :tongue_smilie: This teacher has a pretty good suggestion: http://www.proteacher.org/a/48214_decimals.html Quote Link to comment Share on other sites More sharing options...
lmrich Posted January 3, 2012 Share Posted January 3, 2012 Money. a penny is worth .01 and a dime is worth .1 - it really helps them to see the difference quickly. Quote Link to comment Share on other sites More sharing options...
cschnee Posted January 3, 2012 Share Posted January 3, 2012 Lessons for Teaching Decimals and Percents by Marilyn Burns and TOPS Metric Measuring Quote Link to comment Share on other sites More sharing options...
TracyP Posted January 3, 2012 Share Posted January 3, 2012 We are just hitting decimals... I used mileage as a lead in. If your vehicle has an odometer that your child can view, you can play a game counting the tenths until you hit each mile. I did that by accident, but when we came home I showed her how decimals related to fractions. We have since continued to play the same game when we are going somewhere. CLE also has her doing A LOT with metric measurement as pp suggested. Quote Link to comment Share on other sites More sharing options...
Momling Posted January 3, 2012 Share Posted January 3, 2012 We've just finished the decimals section and it has been surprisingly painless. I think my kids have a much better sense of numbers than I had, so math that confused me is often no problem for them. I did use base 10 blocks for one or two lessons to reinforce some ideas. (It's not 0.07, 0.08, 0.09, 0.010, 0.011), so you might work with them a little if you have them. Also, of course, relating decimals to money helps a lot. Quote Link to comment Share on other sites More sharing options...
AngelBee Posted February 1, 2012 Share Posted February 1, 2012 Need all the help I can get! Taking notes... Quote Link to comment Share on other sites More sharing options...
Dana Posted February 1, 2012 Share Posted February 1, 2012 A decimal that ends or repeats is just another way of writing a fraction. Relating decimals back to fractions also explains why we have the rules we do for decimal arithmetic - especially multiplication. 2/10 + 15/10, we have 17/10... so 0.2 + 1.5, we line up decimals so we're adding like parts. (3/10)(2/10) = 6/100, just like (0.3)(0.2) = 0.06... and look... the decimal moved! It's because we're multiplying two fractions. :) Seems to help with my son. As was mentioned, talking units... 2 TENTHS vs 2 HUNDREDTHS helps with place value too, not just zero point two. Quote Link to comment Share on other sites More sharing options...
Bloggermom Posted February 1, 2012 Share Posted February 1, 2012 There are some great living books that introduce decimals - Fractions, Decimals, and Percents Piece = Part = Portion If You Were a Fraction (Math Fun) Quote Link to comment Share on other sites More sharing options...
Dmmetler Posted February 1, 2012 Share Posted February 1, 2012 We hit 4B, and honestly, it's been easy. You spend enough time on fractions in 4A that the idea that a decimal is just another fraction (and, as DD puts it, an EASY fraction, because the denominator is mostly zeroes) is pretty logical. Doing some chip trading activities with dimes, pennies and dollars can help a lot (or base 10 blocks or chips if your child isn't too rigid-but I've found for my tutoring students that when they've spent K-3 thinking of base 10 blocks as multiples of 1, it's really, really hard for them to think of them as decimals. Money they're used to being subdivided). If you compare to money and think of the 1 as being the midpoint, counting 10ths, hundredths, thousandths, etc makes sense. I ended up giving a lesson on this to a confused mom of a 5th grader at co-op yesterday :). Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.