Greatest Common What?

The Greatest Common Factor (GCF) for two numbers is the largest of the factors that they have in common. The easiest way to understand this is to see some examples...

Find the GCF of 24 and 10:

1. List the factors of each individual number.
24- 1, 2, 3, 4, 6, 8, 12, 24
16- 1, 2, 4, 8, 16

2. Find the highest factor that the two numbers have in common. This is the GCF. Answer = 4

Prime Factorization can be FUN!

By reading the term "Prime Factorization," it does not sound like it is something that is easy to understand, but when you break it down it is actually quite fun! The definition of prime factorization is to write a number as its unique product of primes. This may sound confusing to a young child, so we can teach them how to get the factors of a number through methods. There are two simple methods to find the factors of a number using prime factorization: Factor Trees and Short Division. My favorite method to use is the Factor Tree. I find it the easiest method, peronally, and here is how it works...

The number used in the factor tree is 18. The goal is to find the factors (which wil all be prime numbers) of 18. First, we find two numbers that will multiply to get 18 such as 6*3. 3 is already a prime number, so we just drag 3 down as shown. 6, on the other hand, has multiples (2 and 3), so we draw a branch down from 6 and write 2 and 3. In conclusion our picture turns out looking somewhat like a tree and we have our factors written at the bottom of it. *Note: Never use the top number and 1.

Numbers, Numbers, Numbers...

Knowing the difference between prime numbers and composite numbers is very important in math. These numbers are all whole numbers and fall into one of the two categories besides one. One is considered a unit and is by itself in this category.

Prime Number - A natural number that possesses only two factors, itself and one (One cannot be considered a prime number because the only number it possesses is one).
Examples through 100: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, and 97

Composite Number - A natural number with more than two factors.
Examples through 100: 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, 99, and 100

Who needs video games when there are math games?!

Children start learning addition and subtraction at a young age. Considering most people learn better using pictures, most children are the same way when it comes to learning addition and subtraction. For example, a child would rather use counters then to do math on paper. Some ways that I teach the children I work with addition is subtraction is by using my manipulative kit and having them add or subtract the number of pieces depending on the math problem that I give them. It helps them get a visual of the problem, and makes it a lot easier for them to understand. Another fun way is to play games with children to help them learn. Posted below is one of the math games that a child I work with likes the best.

http://www.playkidsgames.com/games/pinball/addition/addpinballk1.htm

Understanding Number Systems

It is very important for students to understand a variation of number systems! America uses the base-10 number system, but have you ever looked into what other countries may use for their number system? It is actually quite interesting how different some number systems work compared to others. Here are a few videos to help you get a better understanding of how some different number systems work.

There are different ways to get children or people in general familiar with number systems. One way would be to watch videos made by others that describe these systems. Another way such as learning the base-10 and base-5 number systems would be to use visual aid. It is not easy to understand these number systems without actually visually seeing for oneself how they work.

http://www.youtube.com/watch?v=EPIuWjzAHdI Egytian Number System
http://www.youtube.com/watch?v=gJ61QWHCV6E Mayan Number System