DECIMALS: UNDERSTANDING AND IN REAL LIFE

Knight Foundation Summer Institute

Hightail Branch, Wagner Middle School

Jennifer Fisher, Bryn Mawr College

Introduction:

These activities are to reinforce and enrich the understanding of decimals. In these activities, the students must apply basic addition, multiplication, subtraction and division to the new concept. The teacher can begin by teaching the students the basic idea of a decimal. As an introduction, the teacher can bring out a dollar and ask the students how it could be broken down into change. Several products with price tags can also be brought into the class, such as a cereal box, a small toy, a shampoo bottle, etc. The teacher can then explain that the numbers are not always whole. A pretest could then be given to see how much the students already know about decimals. A question comparing the values of several decimals as well as simple adding and subtracting decimals can be on this pretest. After the teacher has completed demonstrating how arithmetic can be applied to decimals, the following activities help to reinforce the lesson.

This lesson contains many activities to build an understanding of decimals through art and games. The students will be exposed to different manipulation techniques that are applied to decimals and will hopefully have fun and enjoy learning in the process. Some of the following activities demonstrate how decimals are used in a real life situation.

Pre-Skills:

  1. Basic skills of arithmetic (addition, subtraction, multiplication, division)

Objectives:

  1. To have the students understand what a decimal is and how it can be manipulated
  2. To have the students be able to complete simple computations with decimals using the arithmetic that they already know
  3. To make the topic enjoyable for the students
  4. To teach the students some practical applications of decimals to make the lesson more relevant to the students' lives

Warm Ups

Exercise #1 Math in Color

Materials:

Procedure:

  1. Distribute the sheets to the class
  2. Explain instructions for the activity to the class
  3. Let the students try to complete the calculations on their own
  4. Offer help after they have made an effort

Exercise #2 Smart Shopping

Materials:

Procedure:

  1. Do a sample problem on the board dealing with finding the price per ounce, ex. 5 ounces for $3, so $0.60 for each ounce
  2. Let the students try the calculations on their own
  3. Offer help after they have made an effort

Class Activities

Exercise #3 Math Jeopardy

Materials:

Procedure:

  1. Divide the class into two teams (Girls vs. Boys might be a good idea)
  2. Ask one team to pick a category (ex. Adding for 100)
  3. Read them the card corresponding to the space that they have chosen
  4. Give them a minute to talk about what they think the answer is
  5. If they are right they get the amount of points for the space that they chose
  6. If they are wrong they lose that many points
  7. The other team then gets a turn
  8. Continue until all of the spaces have been chosen

Exercise #4 Play Store

Materials:

Procedure:

  1. Have all of the students make things; e.g., paper airplanes, drawings etc.
  2. Divide the class in half
  3. Have half of the class put prices, including change, on the objects that the students have made and divide the play money up among the other half
  4. Let the students buy things and play around with the different amounts of change
  5. This can be done twice so that all of the students get a chance to play both roles play money, making

Assessments:

The progress of the students can be tested periodically by short tests requiring the students to do computations with decimals. There can be tests dealing with the individual concepts such as adding, subtracting, multiplying and dividing decimals. At the end of the unit, a test can be given that includes all of the operations as well as the applications to decimals that the students have learned.

A dot to dot exercise where largest one where the students have to follow a path from the smallest number to the largest one

Maze Playing Board and after the students have completed this activity, they can create their own maze playing, boards, hence enforcing the outcome when decimals are applied to different arithmetic operations.

Philadelphia Mathematics Content Standards:

MATHEMATICS CONTENT STANDARD 1- NUMBER SYSTEMS: ARITHMETIC, 'RELATIONSHIPS, AND THEORY

Benchmark two states that students must be able to "develop and use order relations for whole numbers, ..., decimals, ...." From the same section, benchmark seven states that the students must "compute with numbers in a variety of equivalent forms of rational numbers: .... decimals, .... "

MATHEMATICS CONTENT STANDARD - PROBLEM SOLVING AND REASONING

More abstractly here, benchmark two states that students should "apply different problem solving strategies to meaningful problems in home, community and school." This is done through the activity Play Store.

Cross References

These activities help to reinforce how important mathematics can be to the real world. Social interaction dealing with the economy and other money issues is crucial for success, and decimals are a part of this system. Many of these activities also help to enhance the artistic minds of the students' and allow them to use their imagination.