Introducing Greatest Common Fraction (GCF) and Least Common Multiple (LCM) of Fractions
I hope everyone enjoyed their holiday and time off from school. I can not believe how fast the holidays came and went. Like they say, all good things must come to an end. So, with that being said its time to begin a new semester and get back to work.
For this week, I decided to focus on GCF and LCM. For some students, they will struggle with the concept of GCF and LCM because they are not fluent in their multiplication tables. I am currently working with a 6th grade class. They had difficulty with this topic because the entire class was not fluent in the time table at all. Looking back, I know when I was in school, I had difficulty with fractions and finding GCF and LCM as well. However, I was fluent in my multiplication tables, so I feel it was more conceptual for me. After careful consideration, I felt it was important for me to combine the difficulty my student's experienced with my own to formulate this lesson plan I developed.
To begin, I would like to introduce a multiplication refresher course using a YouTube video. This is a fun way of having students learn and memorize the multiplication tables.
https://youtu.be/EgjCLhoI9Mk
Greatest Common Factor
The greatest common factor, or GCF, is the greatest factor that divides two numbers. (http://www.math.com/school/subject1/lessons/S1U3L2GL.html)
To find the GCF of two numbers:
- List the prime factors of each number. (Refer to multiplication facts)
- Multiply those factors both numbers have in common. If there are no common prime factors, the GCF is 1.
Least Common Multiple
A common multiple is a number that is a multiple of two or more numbers. The common multiples of 3 and 4 are 0, 12, 24, ....
The least common multiple (LCM) of two numbers is the smallest number (not zero) that is a multiple of both.
http://www.math.com/school/subject1/lessons/S1U3L3GL.html
The CCLS for 6th grade in this particular topic would be 6.NS
Steps to Locating LCM
After conducting some research, one way to teach this topic is to use the Ladder method.
https://pin.it/6qfxc3ky6giron
1. The above examples I provided will allow me to differentiate and scaffold the lessons for my students.
2. By providing these various methods, I can teach my students all the different ways to find GCF and LCM.
2. The methods I provided will allow students to gain hands-on experience as well as give them the freedom to choose which method is the easiest for them to use.
3. Students can work with accountability partners, which will allow them to communicate different ways of finding GCF and LCM.
Hi Nicole, my third post was multiplication. I agree with you. I believe that multiplication is a critical foundation skill and without the basic understanding a child can experience difficulty on following topics. I also used the multiplication song to help a third grader with multiplication. I love your use of using the acronym of least common multiple as a visual aid for students. I think if I had seen this method when I was learning LMC I believe it would have more comfortable to learn. Visual aids can be handy for students and could be necessary if students cannot understand the standard approach. Great Job Nicole!
ReplyDeleteThank you Chavonna!!! Would you have done or added anything differently? I am curious, did the third grader find it easier to memorize the multiplication tables with the use of the song or using the old flash card method (repetition)?
ReplyDelete