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• MA.4.A.2.1 Use decimals through the thousandths place to name numbers between whole numbers.
• MA.4.A.2.2 Describe decimals as an extension of the base-ten number system.
• MA.4.A.2.3 Relate equivalent fractions and decimals with and without models, including locations on a number line.
Participants will be given a 10 item review exercise on fractions, decimals comparison, estimation and place value.
This exercise will be used to assess participants’ understanding of the teaching and learning of decimals.
Question:
Although we say, “Our” numeration system, is it really ‘ours’?
– Have you ever thought where we got our number system from?
Let’s find out about this Numeration System!
Participants will research and present information about the origin of ‘Our
Numeration System’ and its characteristics.
(Internet Access)
Use of
Zero
Additive
Property
Decimal
System
Base of
10
Place value
NLVM: Use Blocks to represent a number in different bases
Click on the following link and follow the instructions.
http://nlvm.usu.edu/en/nav/frames_asid_152_g_2_t_1.h
tml?from=topic_t_1.html
1. Begin working with base 10.
2. Now try working with 2 other bases. Discuss results!
3. Don’t go to the decimals; we’ll return to this later.
Extra: FunBrain - Place value Puzzler http://www.funbrain.com/cgibin/tens.cgi?A1=s&A2=0
• Base 10 Blocks
Representing numbers with base ten blocks http://www.ulm.edu/~es mith/250/31/repbase10
.html
• Place Value Mat
• Number Strips
1 + 2 + 5
1 hundred + 2 tens + 5 ones
Brainstorming ideas that may be used to encourage students to develop communication skills and express understanding of fractions and place value.
Questions:
How can you relate fractions, mixed numbers and tenth/hundredths?
How can you model tenths and hundredths?
How can you find the value of a digit using its place-value position?
• Where does the word “decimal” come from?
• How many different kinds of decimal units you can form out of a whole.
• Counting numbers smaller than one - why you need a decimal point, and where it goes.
• Find out six ways you can use decimals in everyday life, as well as two reasons that decimals can make math easier.
• The zero and the counting numbers (1,2,3,...) make up the set of whole numbers. But not every number is a whole number.
• Our decimal system lets us write numbers of all types and sizes, using a clever symbol called the decimal point.
• Click on the link below and move your mouse cursor over the decimal number to see its parts.
• http://www.math.com/school/subject1/lessons/S
1U1L2GL.html
Visualizing and developing understanding of decimals
• Download and view the video clip “What is a decimal?
• http://www.onlinemathlearning.com/decimal.
html
Question:
How best can we help students develop understanding of the concept of decimals?
Activity 4
Developing vocabulary power
Purpose: Practice hearing and writing decimals
• Introduce the words for the session
• Divide participants into 4 groups for instruction.
• Each group works on a strategy for developing the mathematical language:
» (i) make a word chart;
» (ii) Vocabulary flash cards;
» (iii) Tree Diagram;
» (iv) Semantic mapping/ a Number Line.
Tens Ones Tenths Hundredths Which is more >, or less <, or equal =?
How would they prove this?
Activity 5: Comparing decimals
Too big or too small: Estimating Fractions
Between 0 and 1
• Provide a model for participants to make that can be used to help them evaluate students' understanding of fractions between 0 and 1.
• Begin by making estimates using familiar benchmarks (e.g., ½, ¼, ¾; 0.5, 0.25, 0.75).
• Provide opportunity for participants to suggest alternative strategies.
Strategy: Act it Out
Alligator Jam Game
This activity will require three students each time the game is played.
• Make the connection that the greater than or less than symbols resemble an alligator’s mouth.
• The alligator is always eating the bigger number!!!! Therefore the
• open part of the symbol will face the bigger number.
• Have two students holding number cards and one student being
• the < or > symbol holding the alligator symbol. The one holding the alligator has the job of eating the bigger number by opening the mouth towards the bigger number. After the alligator has made the decision the audience will decide if the action is right.
• Provide enough opportunities and number cards for each student to have a turn.
Is
?
Directions: For three players.
Mix up the cards. Place them face down on your desk. Each player draws one card. The player with the smallest decimal tells how he/she knows his/her decimal is the smallest.
The smallest decimal wins the round and keeps all three cards. Draw cards until there are no cards left. Each player counts his or her total cards. The player with the most cards wins.
• Participants will use the number line to model equivalent fractions and decimals.
• They will suggest and use other models that allow students to name decimals and place value (NLVM).
This online activity provides a concrete way to introduce equivalent forms of fractions and decimals.
• Participants will construct models to represent a fraction or a decimal.
• Focus on ordering decimals from least to greatest.
Purpose: to examine the problems and judge by observation where the error occurred in the decimal placement of the answers.
Given a set of decimals, participants will identify common errors with decimals.
In groups of 3, participants will identify the error pattern(s), design an activity to remediate the identified problem(s), and present their findings and activity.
Error Patterns
Strengths
• Review content: Communication/Letter writing
Participants write a letter to a friend describing an aspect of the lesson that was significant to them.
• Participants will complete an Evaluation survey
Remember to submit all suggestions.
Participants will:
• Demonstrate understanding of the connection between fractions, and decimals by using prior knowledge of dollars and cents.
• Identify effective strategies for teaching equivalent fractions, writing and decimals/fractions/percent comparisons.
• Examine common errors/difficulties encountered by students when adding and subtracting decimals.
• Identify teacher-specific instructional tools and methods for teaching decimal/fraction/percents comparisons (e.g., models, place value or properties)
• Explore web-based educational resources designed to reinforce learning of writing and relating decimals to common fractions and percents.
• MA.4.A.2.1 Use decimals through the thousandths place to name numbers between whole numbers.
• MA.4.A.2.3 Relate equivalent fractions and decimals with and without models, including locations on a number line.
• MA.4.A.2.4 Compare and order decimals, and estimate fraction and decimal amounts in real-world problems.
Developing Conceptual Understanding of Decimal Numbers
Discuss: How can we help students develop a robust understanding of concepts and symbols?
Provide opportunities for students to:
Communicate its meaning, its use, the results of its application, and its implications for a given context
Make conjectures and justify conclusions
Represent decimals in a variety of ways
Connect decimals to other ideas in and outside mathematics
Know when and how to apply it to solve problems in mathematics and other contexts
Fractions and Decimals in real-life situations
One strategy that may be used to emphasize the importance of decimals is the use of decimals in monetary amounts.
This connection must be made before introducing hundredths: Model& symbol; symbol & word; word model
Model
Symbol (0.3 or 3/10) Word (Three tenths)
Representing Decimal Numbers
• Use physical objects like base-10 blocks to represent decimals
• Draw diagrams to represent decimals
• Connect representations to word form and symbolic form
Connecting Fractions, Decimals and
Percents
1/10 75%
1.25
¾ 0.25 1%
25/100 0.1
0.75 25% 125/100
75/100
12.5%
Percents
To build conceptual understanding:
• Connect percents to decimals and fractions, especially with representations.
• Connect to meanings that students have.
• Use referents that make sense to students, like money and test scores.
What should students know about decimals and percents?
• Understand what the numbers mean
• Understand equivalence and relate decimals to fractions to percents
• Compare decimals and decide the relative size of decimals
• Compute with decimals and percents
• Solve problems involving decimals and percents
Percent Designs
Participants create artful designs that are all one color or another.
• Participants predict the percent of the picture covered by each color, and then they discuss their predictions.
• Participants use grids to figure out the percentages.
Comparing and Ordering Decimals
Skill with comparing and ordering is tied to understanding ideas of equivalence, and to being able to imagine representations for decimals.
• Activity 2. Fraction Game: less than or equal
This applet allows students to individually practice working with relationships among fractions and ways of combining fractions. http://illuminations.nctm.org/ActivityDetail.as
px?ID=18
Activity 3
Fractional Clothes line
• http://illuminations.nctm.org/LessonDetail.aspx?
ID=L784
• This classroom number line will be used to show that all proper fractions are grouped between 0 and 1, and that improper fractions or mixed numbers are all grouped above 1.
Convert From
Decimal To a Fraction http://webmath.com/dec2fract.html
• Participants clink on the above link to access the Decimal converter. The page shows how to convert a decimal into its equivalent fraction.
• http://www.youtube.com/watch?v=RvtdJnYFNhc
&feature=player_embedded
• Fractions to decimals http://www.youtube.com/watch?v=Gn2pdkvdbG
Q&feature=channel
• Factions to Decimals to Percents http://www.youtube.com/watch?v=VlqhVldVces
&feature=related or http://www.youtube.com/watch?v=VlqhVldVces
Activity 4
Selecting a Problem Solving Strategy
Estimating
• Participants will be given a problem that requires them to use an appropriate strategy to estimate the total cost of several items.
They will then justify their answers.
Problem Solving Strategy
Draw a diagram
• Participants use a problem solving strategy to locate decimals, mixed numbers, and fractions on a number line, and convert decimals to fractions.
Problem Solving Strategy
Summarizing or restating
Participants will be given a real-life problem that requires them to connect math and reading.
Participants solve the problem by summarizing or restating the information given.
Participants provide alternative strategies.
Problem Solving Strategy
(RQSCAL)
Using Prompts (RQSCAL)
1. Read the question. R ead
2. What does it mean? Q uestion
3. What will I do to solve it? S trategies
4. Do the maths. C alculate
5. Write the answer. A nswer
6. Look back at the original Problem L ook
Activity 6
Exploring interesting patterns
Using a calculator
Group 1:
Participants will be provided with a calculator and the family of ninths, and ask to find the decimal equivalents (1/9, 2/9, 3/9, 4/9 …).
Group 2:
Participants will use paper and pencil to calculate decimal equivalents for ninths.
Groups discuss the rationale for using each method.
Similarly have participants look at the meaning of 1/3 to help them reinforce the idea that 1/3 is not equal to 0.33, 0.333, or 0.333 (i.e., 1/3 +
1/3 + 1/3 = 3/3 or the whole)
Games
Fractions, Decimals and Percents
Purpose:
To reinforce and practice calculating equivalent fractions and learning the underlying concepts.
Poem
Rounding
• Find your number
• Look right next door
• 4 or less, just ignore
• 5 or more add one more!
Example: Round 123.649 to the nearest 100 th
123.6
4 9 (Find your number)
Look right next door
5 or more add 1 more ( 4 + 1= 5)
Response: 123.649 to the nearest 100 th is 123.67
Conceptual Knowledge
It’s Not!
Learning decimal place value names as verbal labels does not qualify as conceptual knowledge.
It is!
If place value names are related to common fractions, diagrams, and objects of appropriate size, the knowledge is conceptual.
Module Objectives
• Discuss appropriate benchmarks related to decimals.
• Examine common error patterns.
• Explore instructional strategies to help students understand decimals and percents.
• Identify effective strategies for teaching adding and subtracting decimals.
• Identify teacher-specific instructional tools and methods for teaching addition and subtraction of decimals, and addition and subtraction of fractions with like and unlike denominators (e.g., models, place value or properties)
• Explore web-based educational resources designed to reinforce learning of estimating and calculating decimals in tenths, hundredths, and thousandths and relate them to common fractions.
• MA.5.A.2.1: Represent addition and subtraction of decimals and fractions with like and unlike denominators using models, place value, or properties.
• MA.5.A.2.2: Add and subtract fractions and decimals fluently, and verify the reasonableness of results, including in problem situations
• MA.5.A.2.3: Make reasonable estimates of fraction and decimal sums and differences, and use techniques for rounding
Review pre-requisite skills
Brainstorming
• Participants will discuss why developing competency in adding and subtracting whole numbers must be taught before teaching decimals.
• Instructor reviews addition of whole numbers, with and without regrouping …
• Participants will define the words regroup and
ungroup by using each word in the context and by matching visuals to the definition. (E.g., regrouping means the same as ‘trading in’)
Activity:
Distribute activity sheet. Participants may work in small groups/with a partner.
Participants identify student error patterns, and uses the pattern to compute two problems involving addition of fractions with unlike denominators.
Participants discuss the procedure/error and describe 2 instructional activities that may be used to help the student add unlike fractions correctly.
Developing Math Language
Activity 2. Using a Tree Map to review the vocabulary
Vocabulary for this section: fractions, decimals, comparing, finding equivalents, estimate, adding, subtracting, budget, shopping, sums, differences
Activity 3: Word Search/Word Puzzle
The instructor will encourage participants to integrate Language Arts and Math by developing a word search or word puzzle activity to reinforce student grasp of the vocabulary.
Error & Remediation Strategy
Addition and Subtraction
Activity 4: Difficulty with presentation/format of decimal
• Present an example of a problem/difficulty student encounter when adding or subtracting decimals
Yesterday, John ran 5.12 meters, then drove
49.635 meters. What distance did he cover altogether? (e.g., 5. 12 + 49. 635).
Solution: 100.835
Participants identify the problem and suggest remediation strategies
Activity 5
Problem Solving Strategy
Make a Table
Question:
How can making a table help you organize and keep a track of your bank account balance?
Participants will respond to this question by providing examples on the whiteboard to support their claims.
Role Playing
• Examine ways in which students may actively participate in developing a better understanding of the concepts.
1. Given a menu from a local restaurant and a specified amount of spending money, they will select items from a menu and consider whether they want o spend all of the money, some, and the amount of change they should receive.
OR
2. Role play buying and making change. Participants will be divided into two groups (customers and staff). The customer will select the items and place their orders. The staff takes the order and presents the customer with a bill. The customer then checks the bill before paying.
• Discusses the potential benefits of using these activities in the classroom.
Activity 6
Manipulative materials
(Base 10 blocks, 10s and 100s grids)
• Instructor explains the importance of having students work with manipulative materials to develop their understanding of addition and subtraction of decimals
• Participants will explore the use of Base 10 blocks.
Encourage the use of both models: Online and Hands-on manipulative Base 10 blocks.
• http://nlvm.usu.edu/en/nav/frames_asid_264_g_2_t_1.h
tml?from=grade_g_2.html
NLVM: Add and subtract decimal values using base blocks.
Activity 7
Problem of the day: Track Event
Khandi is training to be a long distant runner. She runs once every day. On the first day, Khandi ran a distance of approximately 5 .94 miles. For the next two days she ran an average of 6. 1 miles. Today she ran for the fourth time. Her distance was 6.354 miles. What is the total distance Khandi ran over the four days?
Participants explain what being a long distance runner might entail.
Participants describe how they will assist students in unlocking the problem in order to solve it.
• Discuss with participants how they can use the commutative and associative properties of addition, and the importance of aligning place values when adding or subtracting decimals.
• Participants select a method to add or subtract decimal problems, and discuss the reasonableness of their selection.
Activity 8
Adding and subtracting decimals to thousandths
• The instructor will model presenting problems in both formats: vertical and horizontal. Vertical format should be emphasized to ensure proper placement of the decimal point.
• Participants will be presented with a student’s work sample on addition and subtraction of decimals. They will identify the error pattern and describe how they will help students overcome such problems. They will include the use of manipulative materials/technology in the remediation plan.
Activity 9
Selecting a Method
• Distribute the activity sheet ‘Selecting a method’.
• Participants select a method for each problem and explain the reasonableness of their selection.
(E.g., Mental math, paper and pencil, and calculators)
• Estimate to check reasonableness of
• answer when using a calculator.
• Review content
Individuals present highlights of the session
• Participants complete 10 Item Diagnostic Test and
Evaluation survey.
Thank you for being such a great Team!!