During our first investigation in our unit Factors, Multiples, and Arrays, our classes have created posters of the arrays for various numbers. Using these posters, we have put numbers into different categories based on the kind and number of arrays they could make.
We have identified numbers that can make "only one array", numbers that make "square arrays", and numbers that make "many different arrays". These initial ideas have now developed into classifying numbers in five ways: odd, even, prime, composite, and square. Numbers may fall into as many as three different categories.
Here is a list of the mathematical ideas that are being developed during Math Workshop as a result of these student-made posters:
Odd Numbers: * have a 1, 3, 5, 7, or 9 in the ones place * have only odd factors * odd x odd = odd
Even Numbers: * have a 2, 4, 6, 8, or 0 in the ones place * always have a factor of 2 * each factor pair must have at least one even factor * odd x even = even, even x odd = even, and even x even = even
Prime Numbers: * only have 2 factors (one and itself) * only produce one array * 2 is the only even prime number
Composite Numbers: * have more than two factors * make at least 2 different arrays * can be even or odd
Square Numbers: * make a square array * have an odd number of factors * follow a pattern of odd, even, odd, even, ... * can be made by multiplying a number by itself (ex: 1 x 1 = 1, 2 x 2 =4, 3 x 3 = 9, therefore, 1, 4, and 9 are square numbers)
Students, can you identify a number between 100-200 that is composite and square? Leave a comment and share your answer (and your reasoning) and you will earn Behavior Bucks!!
We have identified numbers that can make "only one array", numbers that make "square arrays", and numbers that make "many different arrays". These initial ideas have now developed into classifying numbers in five ways: odd, even, prime, composite, and square. Numbers may fall into as many as three different categories.
Here is a list of the mathematical ideas that are being developed during Math Workshop as a result of these student-made posters:
from Brody, I think that 144 works because 12 times 12 =144, and because 144,s factors are 1, 2, 3,4,6, 12, and 144 atleast
ReplyDeleteabdelrahman, 100 works because it is the square of 10 (10x10) and has more than two factors (1x100),(10x10)
ReplyDelete100 144 196 are both square and composite. 100 is 10 x 10 but is also 2 x 50 and 4 x 25 and 5 x 20 and 1 x 100. 144 is 12 squared, 1 x 144, 2 x 72, 3 x 48, 4 x 36, 6 x 24, and 8 x 18. 196 is composite and square - 14 squared, 2 x 98, 4 x 49, and 7 x 28.
ReplyDeletealex