dysTalk Teaching Fractionsmath In General - Dyslexia - Forum - dysTalk

My dyslexic son is having a hard time remembering how to do frations. One day he can do the work, the next day he can't seem to remember. Just when it seems like he understands and remembers, it's gone. Help!!!

30/11/2010 20:04:10
Cherie

The multiplication of fractions is the easiest (1/4 x 1/4 becomes 1 times 1 = 1 and 4 times 4 =16 ... the answer is 1/16). To remember these are the easiest associate the x symbol with a kiss ... multiplication is the one you love because it is easiest ... kiss,kiss,kiss.

The division of fractions (1/4 divided by 1/4) requires the second fraction to be flipped over before it them becomes a multiplication sum: 1/4 x 4/1 (one that you love). To remember this move, play around with the division sign, flipping the dots ... the division symbol then triggers the flipping move for future sums.

The addition and subtraction of fractions are the tricky ones. I believe the problem here is that children espect addition and subtraction to be easy, because they are the ones they are most familiar with when dealing with whole numbers. Just pointing out to your son that fractions are devious to remember because they go against our expectation can help him recognise why he's found them difficult / confusing.

Adding 1/4 and 1/3 is the same as adding a giraffe and an elephant ... it can't be done until you turn both of them into something they both are (animals). Play around with this asking each other questions so your son gets used to the idea of changing different things into a shared group.

The easiest way to change 1/4 and 1/3 into a common denominator is to multiply the bottom numbers together (12). Then draw a brick wall. On one layer draw 4 bricks (each is 1/4 of the wall's width), on another layer draw 12 bricks (each brick is 1/12 of the width of the wall. How many of the 1/12 bricks is the same as one 1/4 brick? The answwr should be 3. So now your son can change 1/4 into 3/12. Do the same for a layer of 3 bricks. How many 1/12 bricks equals a 1/3 brick? The answer should be 4. So 1/3 can be changed to 4/12 ... now add 3/12 and 4/12 to make 7/12 (the same as adding 3 cats and 4 dogs to make 7 animals).

When you then get an answer which is, say, 13/12, go back to the wall and explore what that would mean. Discover that 13/12 means one wall plus a brick left over to start the next wall = 1 and 1/12.

Play with walls. Use colour to make them more interesting. Draw a large wall with different layers, colour each layer, cut out the bricks, take turns to put the wall back together again against the clock.

Discuss and explore patterns and links between different layers in the walls. If you have a layer 10 bricks across, and one of 3 bricks across, what is the problem?

You can make walls which share patterns (eg 10, 5, 2 ... 20, 10, 5, 2 ... 12, 3, 4, 6, 2).

Sorry for length.

Have fun!

22/12/2010 23:15:35
Sally Raymond