Cheryl Fitts - Adding Tenths Lesson Plan

written by: Cheryl Fitts (Spring 2001)
graphics, editing, & formatting by: Dr. Beth McCulloch Vinson

Subject: Adding tenths

Grade: Three

I. Behavioral Objective:

After a teacher-directed math lesson, the students of Mrs. Fitts’ third-grade class will: pictorially represent the tenths place with decimal bars and add decimals in the tenths place. Each student will use decimal bars to represent tenths and solve simple addition problems with the tenths place. Each student will add tenths at an accuracy rate of at least 90%.

II. Instruction/Method:

A. Anticipatory Set:

1. Explain that today they will learn to add tenths.

2. Read the book The Patchwork Quilt.

3. Express the importance of adding tenths in everyday life, such as sharing.

4. Use square regions to refresh the students on decimals and to build on that to explain adding tenths.

5. Supply the following definitions to ensure understanding: “decimals” and “tenths”.

B. Statement of Objective:

“When we finish today you will perform simple tenths addition.”

C. Instructional Input:

1. Review how to correctly name decimals and how to line numerals vertically.

2. Illustrate simple addition with tenths, for example 0.1 + 0.3 = 0.4

3. Using a transparency on the overhead projector, bring out the meaning of the word “decimals” at this time.

D. Modeling:

1. Illustrate the proper method of making decimal bars and the parallel between decimal bars and adding tenths.

2. Using a transparency on the overhead projector, share the following word problem with the class to illustrate adding tenths. “Cassie colored two tenths of her decimal bar with a green crayon and Mark colored three tenths of his decimal bar yellow crayon. How many tenths did they color together?” Point out the use of decimals in this problem.

3. Show the children the symbolic representation of the decimal bar on the poster board (0.2 + 0.3 = 0.5).

E. Checking for Understanding:

1. After sharing the word problem, ask the students to figure out how many tenths of the decimal bar they have colored. The children will have each colored five tenths of their decimal bars.

2. Quiz the children on their responses and the reason for those responses.

F. Guided Practice:

1. Place students into groups of two. Instruct the children to bring their decimal bars and crayons to their group.

Group Numbers:

1,3,5- One student should color two tenths of the decimal bar while the other colors six tenths. Combine the decimal bars and tell the actual addition problem you have solved.

2,4,6- One student should color three tenths of the decimal bar while the other colors five tenths. Combine the decimal bars and tell the actual addition problem you have solved.

7,9,11- One student should color four tenths of the decimal bar while the other colors one tenth. Combine the decimal bars and tell the actual addition problem you have solved.

8,10,12- One student should color four tenths of the decimal bar while the other colors three tenths. Combine the decimal bars and tell the actual addition problem you have solved.

G. Independent Practice:

1. Instruct children to get a Bingo Blitz card and chips.

2. Ask the children to randomly fill in the blank boxes with tenths.

3. As I write a simple tenths addition problem on the board they will answer the problem on scratch paper. If they have that sum on their cards, they will place a chip on that block. We will play until we have a winner.

1. Strategies to use with Exceptional Children:

a. For enrichment, increase the numeral value in the tenths place so that there is a numeral to be carried. In other words, the decimals add to more than one whole.

b. For remediation, the children will practice relative size.

2. Activities which Value Cultural Diversity:

Children who speak English as a second language will add their equation for the class in their primary language.

3. Activities which Foster Active Inquiry, Critical Thinking, and Problem Solving:

a. Ask the students to bring objects from home to use in tomorrow’s lesson to display adding tenths. Some items might include: a pack of gum or a pack of crayons.

b. The children will be asked to complete a worksheet that uses answers from adding tenths to decode an answer to a riddle.

H. Closure and Summary:

1. Bring the session to a close by having the children orally relate their addition problems, their sums, and their answer to the riddle.

2. Ask the children to look for opportunities to use this new skill at home with spokes on their bikes and their fingers and toes.

III. Assessment Techniques:

The students of Mrs. Fitts’ third-grade class will add the tenths place at an accuracy of at least 90%.

It must be determined whether a child understands the concept of addition and place value as prerequisite skills. In order to conclude whether the children could add, the teacher could use the abacus to quiz the children. In order to confirm the children’s understanding of place value, the teacher could use place value blocks to quiz the children.

IV. Materials:

an abacus, 24 copies of decimal bars, 24 copies of square regions, key word transparency, word problem transparency, set of pictures for the word problem, overhead projector.

Book: Flourney, V. (1985). The Patchwork Quilt. New York: Dial Books. (ISBN: 0-8037-0097-0)

Also, see the Fractions and Decimals PowerPoint Slides Shows at:

http://www.athens.edu/pt3/vinson/fract_dec.ppt

http://www.athens.edu/pt3/vinson/fract_set.ppt

See the Addition PowerPoint Slide Shows at:

http://www.athens.edu/pt3/vinson/addition_r.ppt

http://www.athens.edu/pt3/vinson/addition.ppt