The math is not in the model to be seen but in the learners head. The learner is constantly trying to figure out and understand. Use real context this will give the opportunity for authentic learning.
So you teach fractions here are some strings for you
Think about a half? Elicit responses from your community. Many will come out but the first one I want you to think about is money.
First string think about $$
String 1 (coin strings)
1.) ½ + ¼ = (3/4 75/100)
2.) ½ +1/10 = 6 dimes 60 cents
3.) 2/10 + 1/5= (how many people thought of a nickel)(good for /100)
4.) 4/10 + 2/5 +1/4=
This is a very early string for fractions. These are landmark fractions. Landmark fractions are easy because you are dealing with whole numbers instead of dealing with fractions. Link to percents because of the $1.00. Get rid of the fractions and make it contextual.
String 2 (clock)
Draw the clock to represent the fraction
Calculate the minutes. You do not need to show the equivalent fractions because the clock model is there you do not need to show the equivalent fractions
1.) ½ + 1/3
2.) ¼ + 1/3 (anyone get 7/12)
3.)1/6 +3/12 +1/3
(1/6 is the kicker here) 1/6 is 10 minutes… start to look at the whole.. There was some breakdown here. The 1/6 was causing problems… get the community to provide the proof for the breakdown. This is key keep the kids talking and doing the explaining. Knowledge can be generated out of a communities talk. 4) 10/60 + 1/6 +1/4 +7/12
This problem was generated after the community was having issues. Free flow. Getting bogged down in some lcd’s
Pedagogy 10/60 and 1/6 are = this should be a good scaffold
When doing strings think on your feet and go with the flow… but not too much
This string again gets you away from fractions and into wholes… then you can get back into the fractional form.
Scaffold the landmark fraction(ability to use whole numbers) and coins.
String 3 (you choose the strategy)
Look at the numbers and choose coins or clocks
1.) ½ +1/3 (clock because of 1/3 $)
2.) 1/3 +1/4
3.)¼ + 1/5 ($$)
4.) 4/5 – ¼ ($$ because of the /5)kids will start to see which fractions are clockable and which are $$able
String 4 (double numberline)
Pick any number you want to be a guide on the track (numberline)
1.) 1/3 + 1/7 =
2.) ½ +1/4= Community will choose numbers to be the numberline total
(need to add the other aspects of the string) Kids will start to create common denominators What others numbers are easy numbers Lets pick a simpler number…. This gets to the common denominators. Work to prove conjectures. Name them after the student that came up with the idea. Use other examples to prove or disprove Double open numberline paves the way to common denominators…… Push to show equivalence
String 5 (Use an array to demonstrate)
1.) 1/3 x 1/5 left with 1/15(outer inner boxes)
2.) 2/5 x 1/3 (the whole remains the same one more piece doubles)
3.) 2/5 x 2/3 (double doubles) (use the playground context to be the building block)
Inner and outer rectangles show the algorithm
4.) 3/5 x 2/3 You can use the previous array (shows the pattern)
5.) 2/5 x 3/3 Curious leap here (new array) what happened to the inner rectangle. It shifted 2 by 3 becomes 3 by 2)
Can we swap the numerators to make a friendly question
6.) 4/7 x ¾ = 3/7 x 4/4
Division of Fraction
Use a ratio table see photo Use the ratio table to explain yours is not to reason why just invert and multiply
The use of the ratio table was brilliant. It should be the model used to bring understanding to why we invert and multiply fractions.
Many times we take part in activities and professional development that is lacking in so many ways. These 3 days out of my summer break were stimulating and exciting. I can hardly wait to use my knowledge of 2.0 apps and push the limits of what I learned this weak. Oh Yeah you can annotate and draw while doing a voice thread. That is too cool for school.
For those of you who want to get the Fosnot material here is the web address
The material I was being taught is from Fractions Decimals and Percents.