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Algebra Stumbling Block

I’m doing a bad thing.

Some of my algebra kids are stumbling over fractions. They’ve been befuddled by them for 4 years, and freak out when they see them.

So, I’m teaching them some very basics.

1) Multiplying a fraction and a whole number: Divide by the denominator, times the top. Aka !http://l.wordpress.com/latex.php?latex=\frac{\times}{\div}!. 90% of the fraction problems they’ll run into in algebra involve this.

2) Cancel fractions by multiplying by the reciprocal. Sure, this is the same as dividing, but that extra having to remember seems to throw them.

I feel somewhat cheap doing this, but I can’t spend a lot of time doing remedial work, so I’m trying to focus on the parts that allow them to meet the standards for the class that they’re in. It’s odd – a lot of them prefer to think in decimals, but that breaks a lot of what we do. I’m hoping that these two simplifications will reinforce the use of fractions, and provide support for when they try to remember all the other fraction stuff.

We’ll see.

{ 4 } Comments

  1. Sarah | September 29, 2008 at 6:01 am | Permalink

    Oh and if they do know how to work with fractions, improper fractions must always be converted to proper fractions. I keep wanting to say, “Sorry, but that step’s not critical to our work, so we’re not going to make sure your classmates learn it.”

  2. N.D. | September 29, 2008 at 7:04 am | Permalink

    Most of my algebra 2/geometry/precalc students struggle with fractions. Do they not hit them enough in middle school? I’m tired of fraction phobia.

  3. Mr. K | September 29, 2008 at 9:12 pm | Permalink

    @ND For us, fractions are 6th & 7th grade standards. There is a heavy emphasis on converting to decimals and percents.

    That’s why I’m picking out the subset of rules they’ll need to function well. I think it’s one of those things where, if you can get them to use them regularly, and easily, they’ll lose the fear. Then, because of all of the distributive property & combining like terms stuff they’ve had, the adding rules will come more naturally as well.

    @Sarah I really want to teach them to keep everything as improper fractions, but that’ll handicap them on the tests. But they only need to know how to convert – actually doing math with mixed numbers causes more work than reward, I believe.

  4. Fluxion Fred | January 3, 2011 at 9:19 pm | Permalink

    It is no surprise that they prefer decimals. This is the type of number that appears in their calculator. This machine validates so much of what they do.

    I also try to get the students to keep their fractions improper. However, mixed numbers are handy for checking for reasonableness. We need to have the students report fractions in improper form, but use conversion to mixed number for checking work.