TitleIII Technology Literacy Challenge Grant

Learning Unit

Overview | Content Knowledge | Essential Questions | Connection To Standards | Initiating Activity | Learning Experiences | Culminating Performance | Pre-Requisite Skills | Modifications | Schedule/Time Plan | Technology Use

LU Title: Understanding and Applying Percents

Author(s): Michael Calandra

Grade Level: 7

School : Camden Middle School

Topic/Subject Area: Percents/Mathematics

Address: 32 Union Street

Camden, New York

Email:mcaland@camden-csd-admin.moric.org

Phone: (315) 245-0080

Fax: (315) 245 -0083

 

 

OVERVIEW

One need not look far to see that percent applications surround us. Like our students, we have all experienced occasions when we overlook what stares us in the face. This unit is intended to first direct attention to the prevalence of percents, and then to develop a working understanding of them. As outlined in Understanding by Design teachers must establish curricular priorities. The premise for this learning unit is that percents are both "enduring" and "at the heart" of the grade 7 mathematics curriculum. Although this unit includes a significant amount of skill development, the main thrust will be to establish a base for meaningful and long-lasting understanding for the application of percents.

(It should be noted that this unit requires integration with an ELA instructor.)

(www.askjeves.com and www.dogpile.com are excellent search engines to find both dining and shopping locations.)

 

 

CONTENT KNOWLEDGE

Declarative

Procedural

  • Students will understand that percents have numerous applications.
  • Students will write an essay identifying where one may "run into %'s." It will conclude with a persuasive statement substantiating why percents are necessary.
  • Students will understand that a percent is a comparison.
  • Students will be able to write any percent as a ratio or decimal.
  • Students will understand "%" is a symbol that represents "compared to 100"
  • Students will be able to write any percent as a ratio or decimal in simplest form.
  • Students will understand that common fractions/ratios can be expressed as %'s.
  • Students will be able to express common fractions as percents.
  • Students will understand that Decimal fractions can be expressed as %'s.
  • Students will be able to express decimal fractions as percents.
  • Students will understand that "Base" represents the whole.
  • Given the percent & percentage, students will be able to determine the base.
  • Students will understand that"Percentage" is the designated part of the whole.
  • Given the percent and base, students will be able to determine the percentage.
  • Students will be able to recognize a percent sentence e.g. 25% of 80 is 20
  • Students will be able to express fractions as decimals.
  • Students will recognize reference percents: 100%, 75%, 50%, 25%, 10%
  • Students will be able to make mental calculations for basic questions asking for the percentage, base, and percent
  • Students will recognize multiples of 10%, and 5%
  • Given the base and percentage, students will be able to determine the percent
  • Students will understanding "percent off" and "percent on"
  • Students will be able to determine the percent of increase/decrease
  • Students will understanding why percent is used to represent tax and tip.
  • Students will be able to calculate the percent of and amount of interest.
  • Students will understanding why percent is used by retailers.
  • Students will be able to determine the percent of and amount of commission.
  • Students will understanding the misconception of multiple percent discounts e.g. 50% off plus an additional 25% off is not equivalent to 75% off
  • Students will be able to determine discount, tax, and total cost

 

  • Students will be able to determine the cost of dining out - Meal + Tax + Tip.

 

  • Students will be able to compute the difference between multiple percents and the corresponding total percent. e.g. 50% off plus an additional 25% off compared to 75% off

ESSENTIAL QUESTIONS

 

  1. What are the advantages of using percents as a standardized means of making comparisons?
  2. Mental math lends itself to "solutions at the ready." What benefit might this provide for one when dealing with percents in a store, restaurant, bank, or school?
  3. How does understanding percents make one a "smart consumer"?

 

CONNECTIONS TO NYS LEARNING STANDARDS
List Standard # and Key Idea #: Write out related Performance Indicator(s) or Benchmark(s)

MST 1:

Key Idea 1- Mathematical Analysis: Abstraction and symbolic representation are used to communicate mathematically.

Performance Indicator: Students extend mathematical notation and symbolism to include variables and algebraic expressions in order to describe and compare quantities and express mathematical relationships. This is evident when students create an equation to solve real life problems involving percents.

Key Idea 2- Mathematical Analysis: Critical thinking skills are used in the solution of mathematical problems.

Performance Indicator: Students apply mathematical knowledge to solve real-world problems and problems that arise from the investigation of mathematical ideas, using representations such as pictures, charts, and tables. This is evident when students compare the sum of multiple percents off vs. the equivalent total. E.g. 50% off plus and additional 25% off compared to 75% off

 

MST 3:

Key Idea 1- Mathematical Reasoning: Students use mathematical reasoning to analyze mathematical situations, making conjectures, gather evidence, and construct an argument.

Performance Indicator: Students will apply a variety of reasoning strategies. This is evident when students use multiple means for solving percent related word problems, such as 25% of 80 is __ = .25 (80) = X or 25/100 = X/80

Key Idea 2 - Number and Numeration: Students use number sense and numeration to develop an understanding of the multiple uses of numbers in the real world, the use of numbers to communicate mathematically, and the use of numbers in the development of mathematical ideas.

Performance Indicator 1: Students understand, represent, and use numbers in a variety of equivalent forms. This is evident when students understand and demonstrate the concept that a number can be symbolized by many different numerals as in: 3/12=1/4=25/100=.25=25%.

Performance Indicator 2: Students understand and apply ratios, proportions, and percents through a variety of hands on exploration. This is evident when students are able to identify and solve real world problems involving percents.

Performance Indicator 3: Students develop an understanding of number theory (primes, factors and multiples). This is evident when student are able to simplify expressions.

Key Idea 3 - Operations: Students use mathematical operations and relationships among them to understand mathematics.

Performance Indicator: Students apply concepts of ratio and proportion to solve problems. This is evident when students find the missing number in a proportion in which three of the numbers are known, and letters are used as placeholders.

Key Idea 4 - Uncertainty: Students use ideas of uncertainty to illustrate that mathematics involves more than exactness when dealing with every situation.

Performance Indicator 1: Students use estimation to check the reasonableness of results obtained by computation, algorithms, or the use of technology. This is evident when students are able to use "reference percents" to make mental calculations.

Performance Indicator 2: Students use estimation to solve problems for which exact answers are inappropriate. This is evident when students estimate a reasonable "tip" when dining out.

Key Idea 5 - Patterns/Functions: Students use patterns and functions to develop mathematical power, appreciate the true beauty of mathematics, and construct generalizations that describe patterns simply and efficiently.

Performance Indicator: Students develop an understanding of functions and functional relationships: that a change in one quantity (variable) results in change in another. This is evident when students solve real life problems involving percents.

 

 

ELA 1

Key Idea 1 - Speaking an Writing: Speaking and writing to acquire and transmit information requires asking probing and clarifying questions, interpreting information in one's own words, applying information from one context to another, and presenting the information and interpretation clearly, concisely, and comprehensibly.

Performance Indicator: Students produce an oral and written reports on topics related to all school subjects. This is evident when students orally present to their classmates and write an essay that contains information from a variety of sources.

 

 

INITIATING ACTIVITY

 

Students will be required to collect five to eight examples of "real world" percents. An essay must be written indicating where the application of percent is used and conclude with a persuasive statement supporting the value of them. The following resources may be referenced: newspaper, magazines, Internet (hard copy), or a television advertisement (drawing). Students will be placed in cooperative triads. Each member will be required to discuss his/her contribution and the team will then create a collage. These will be graded and displayed in the classroom.

 

 

 

LEARNING EXPERIENCES
In chronological order including acquisition experiences and extending/refining
experiences for all stated declarative and procedural knowledge.

 

Declarative and Procedural Knowledge

 

Strategies used to help students construct meaning, organize and/or store knowledge

 

Experiences or activities used to:

Help students acquire and integrate knowledge.

 

 

Assessment

 

Day 1- Developing an understanding of percents.

 

Prior knowledge

Cooperative group brainstorming Teacher gathering of group input. KWL

 

Homework (see initiating activity) Instructor will outline expectations for this four week unit.

 

Teacher observation Essay question

 

Days 2,3 1.Compilation of data for collages 2.Writing percents as ratios and decimals 3.Writing ratios and decimals as percents

 

Cooperative groups Review of homework Notetaking Class discussion

 

Instructor led discussion related to submissions. Homework Instructor will present models for each of the requirements.

 

Collages will be graded and displayed Teacher observation In-class Performance tasks/Homework

 

Days 4,5,6

Solving three cases for percents.

Cooperative groups Peer Review of homework Instructor led review of homework Notetaking

 

Homework Model solutions

 

In-class Performance tasks Homework

Days 7,8 Developing understanding: 1. Reference percents 2. Percent on / off 3. Identifying base, percentage, percent

 

Cooperative group game "Thinking Pads On Calculators Off - Name That Value"

 

Guided practice Homework

 

Teacher observation In-class Performance tasks/Homework & Quiz

Days 9, 10 Developing understanding for real world problems missing the percentage. 1.Amount of discount 2. Amount of interest 3. Amt. of commission 4. Amount of tax 5. Amount of tip

 

 

Solutions presented by students at the board or overhead

 

 

Instructor presents and models solutions. Guided practice

 

 

Teacher observation In-class Performance tasks/Homework & Quiz

Days 9,10 Developing an understanding of real world problems missing a percent. 1. % of commission 2. % of interest 3. % of tax 4. % of tip 5. % of increase/dec.

 

 

Peer review of homework

 

 

Instructor presents and models solutions. Guided practice

 

 

Teacher observation Performance tasks/Homework & Quiz

Days 11,12 Developing an understanding of real world problems missing a base. 1. Original price 2. Principal 3. Total sales

  

Solutions presented by students at the board or overhead

 

Instructor presents and models solutions. Guided practice

 

 Teacher observation Performance tasks/Homework & Quiz

Day 13 Developing an understanding of multiple %'s off vs. the total corresponding %

 

Cooperative group solutions Homework

 

 Guided discovery

 

Teacher observation Performance task Homework

Day 14,15,16 Collecting and organizing of data for culminating activity

Technology lab Internet research

 

Guided discovery

 

Culminating activity

Day 17, 18, 19 Oral presentations Day 20 (Buffer)

Rehearsed with parent

Oral presentation

Teacher Evaluation

Self assessment

 

 

CULMINATING PERFORMANCE
Include rubric(s)

 

Students will have a choice of either "Dining Out, " or having a "Sports Related Shopping Spree" on the Internet.

Dinner

Five dinners representing at least three different cultures

The following items must be listed for each dinner - Drink, entrée, and dessert

Calculations must be determined for meal, tax, tip, and total expenditure for each of the five days.

One dinner must be selected for an oral presentation. Part of this presentation must include a "walk through solution."

 

Sports Shopping Spree

Shop on the web to purchase clothing and equipment for two sports

Must include at least two sale items for each sport

Percent of savings and amount of savings must be determined for each

Total bill must be calculated, including shipping and handling

Shipping and handling must also be expressed as a percent

If no tax is charged, 8% is to be used to determine the approximate amount of savings due to no tax.

An oral presentation must be reflect why a sale item was purchased. Part of this presentation must be a "walk through solution.."

 

 

PRE-REQUISITE SKILLS

Percents are first introduced to students in grade 5 . This important concept continues to be spiraled through intermediate and commencement levels. Although all students will recognize and be able to perform some skill functions, they will need to be broadened and refined.

 

MODIFICATIONS

 

  

 

TECHNOLOGY USE

1. Student essays must be completed using word processing software.

2. The worldwide web will be utilized to gather necessary data to complete the culminating performance. An introductory level of Internet sophistication will be necessary to satisfactorily complete this requirement.

Culminating Performance Self-evaluating and Teacher Rubric

 

Requirements

All required solutions are clearly presented.

All required solutions are included but not well organized.

One of the required solutions is not included.

Two or more of the required solutions are not included.

Process

All solutions formatted correctly.

One or two problems set up incorrectly.

Three problems set up incorrectly.

More than three problems set up incorrectly.

Accuracy

All solutions are accurately calculated.

90% of the calculations are correct.

75% of the calculations are correct.

Less than 75% of the calculations are correct.

Oral Presentation

Presentation is clearly stated and demonstrates understanding of concepts.

Presentation is complete but lacks clarity of understanding.

Presentation contains errors and lacks clarity and understanding

Presentation is not attempted.