FUTURE MATHEMATICIANS

Building upon Subtraction SkillsBy Janelle McIntosh

Subtraction IntroductionGreetings First Graders, I’m your teacher Mrs. McIntosh. My goal is for you to become stronger in subtracting numbers.

I feel you’re good at adding to another number, so now it is time to move on to taking away from a number.

SUBTRACTIONHELPFUL HINTS

•subtraction is the opposite of addition

5-3= 2 3+2=5 5-2=3 2+3=5

•When subtracting your answer is smaller then the first number2 is smaller than 5 and 3 is smaller than 5

•Please take the time to memorize your subtraction facts. It’s like riding a bike…once you learn, you’ll never forget.

Subtraction Vocabulary

6-4=2Difference: the answer to the subtraction problem

Minuend: the first number you see in a subtraction problem

Subtrahend: the number you take away from the first number

Subtraction Song

To the left, to the leftWhen we subtract, we go to the left To find the difference, we go to the left

Subtraction Number LinePart 1

0 1 2 3 4 5 6 7 8 9 10Start 8Jump -4Land 4

Subtraction Number LinePart 2

0 1 2 3 4 5 6 7 8 9 10Start 10Jump -7Land 3

Subtraction TrianglesPart 1

5

4 1

5-4=1 5-1=4

Subtraction TrianglesPart 2

9

2 7

9-7=2 9-2=7

Subtraction Story Problem 1

1. A turkey grew 7 feathers. On the way to the Thanksgiving party, he lost 2 feathers. How many feathers are on his back, now?

________ -________= ________

Subtraction Story Problem 2

1. Billy came to school with 4 pencils. He gave away 2 pencils. How many pencils did he come home with?

________ -________= ________

Subtraction: Find the Missing number

1. 9- = 3

2. 10- = 5

3. 6- = 1

Subtraction Quiz

Procedure for Partner PracticeRally Robin• Students will sit with their assign partners and quiz each other with their self-made flash cards• Students will previously know their assign number 1 0r 2, so they know who’s going first• Student number 1 will show the first subtraction fact without revealing the answer. Student number 2 will get 3 guesses before the answer is revealed• Now, its student number 2’s turn to show a subtraction fact repeating the same step as above• Take turns, whisper voices, always working, work together

Procedure for Group PracticeRound Table• Students will use a dry-erase board and a

dry-erase marker to respond to a numbered subtraction problem• Each student will have an assigned number 1-4, so they will know the order of when it is their turn to write• Each group of 4 will be given a sheet with 5 subtraction facts to respond to one at a time• Every group member will have their opportunity to give their opinion of the subtraction problem, then students must discuss why or why not the problem is correct• take turns writing, be different, explain your answer,whisper voices , respect others opinions

Websites for Practice

Subtracting 3’shttp://www.ixl.com/math/grade-1/subtracting-3

Subtraction Number Line Song http://www.youtube.com/watch?

v=VZh6p3kUdyA

Subtraction Frog Gamehttp://www.coolmath-games.com/0-feed-fribbit-subtraction/index.html

Works Cited- Page 1Slide 1: teacher pictures is from http://www.picturesof.net/search_term_pages/math_teachers.html Number Picture is from www.clipartpal.com

Slide 2: Light Bulb and student riding bike is from Microsoft Clipart

Slide 5: Music note is from Microsoft Clipart

Slide 10 : Turkey is from Microsoft Clipart

Side 11: Pencils is from Microsoft Clipart

Slide 12: Rain drop is from http://www.clipartguide.com/_pages/1386-0906-2708-5134.html

Slide 13: screenshot from www.enchantedlearning.com

Slide 14: students are from Microsoft Clipart

Slide 15: group circle is from www.trishnasumal.wordpress.com

Works Cited- Page 2Slide 14-15: Rally Robin and Round Table comes from Kagan Structures for engagement www.KaganOnline.com

Slide 16: Subtracting 3’s Quiz is from www.ixl.com Number line Song was created by Peter Weatherall from www.youtube.com

Frog Subtraction Game is from www.coolmath.comcreated by Cool math Karen and Leah