Eureka Math Tips For Parents Module 1 Sums And .

Eureka Math Tips for ParentsSums and Differences to 20Inthis first module of Grade 2, we setthe foundation for students tomaster sums and differences to 20.They will then apply these skills tofluently add one-digit to two-digitnumbers up through 100, usingplace value understanding,properties of operations, and therelationship between addition andsubtraction.A new way to count! How you canhelp at home: Review with your studentall the ways to make 10;students will need tohave these memorized aswe work through thismodulePractice “10 plus”problems, such as 10 9,20 8, 40 6, 70 7,and so on, so that yourstudent becomes veryadept at doing themmentally and quicklyTerms, Phrases, andStrategies in this Module:STRATEGY: Make ten andsubtract from ten – strategy inwhich students decompose anumber in order to make a ten,thus using simpler, known factsto solve the problem, e.g.,8 3 8 2 1 and15 – 7 10 – 7 5 3 5Above, an illustration of the “SayTen” way of counting, in whichstudents name how many tensare in a number and then say theones.What Comes After thisModule: In Module 2, studentsThe “make a ten” strategy: notehow 4 is decomposed as 1 and 3in order to make a ten, i.e., 9 1 3 10 3.Grade 2Module 1will engage in activities designedto deepen their conceptualunderstanding of measurementand to relate addition andsubtraction to length. They willuse metric units in this module;customary units will beintroduced in Module 7.STRATEGY: Say ten counting e.g., 11 is “1 ten 1,” 12 is “1ten 2,” twenty is “2 tens,” 27 is“2 tens 7,” 35 is “3 tens 5,”100 is “10 tens,” 146 is “14tens 6”Ten plus: number sentences inwhich students automaticallycombine one addend with thegroup of 10 without having tocount, e.g., 10 3 13, 30 5 35, 70 8 78Number bond: used to explorethe part/whole relationshipswithin a given number, e.g.,for the number 6:5 1 6,1 5 6,6 – 1 5,6–5 1Key Common Core Standards: Represent and solve problems involving addition andsubtractiono Use addition and subtraction within 100 to solve one- andtwo-step word problems Add and subtract within 20o Fluently add and subtract within 20 using mentalstrategies Use place value understanding and properties of operations toadd and subtracto Fluently add and subtract within 100 using strategiesbased on place value, properties of operations, and/or therelationship between addition and subtractionPrepared by Erin Schweng, Math Coach

Grade 2Module 1Eureka Math, A Story of UnitsWelcome to A Storyof Units!Number Bonds are a tool first introduced in earlier years of AStory of Units. They illustrate a part-part-whole relationship andare very useful in this module as students use the “make a 10”strategy for both addition and subtraction.Each module’sparent tip sheet willhighlight a newstrategy or mathmodel your studentwill be working on.In the above problem, the number bondsillustrate how to decompose the numbers inorder to make 80 7 3 2, or 80 10 2,or 92.Read on to learn a little bit about Eureka Math, the creators of A Story of Units:Eureka Math is a complete, PreK–12 curriculum and professional development platform. It followsthe focus and coherence of the Common Core State Standards (CCSS) and carefully sequences theprogression of mathematical ideas into expertly crafted instructional modules.This curriculum is distinguished not only by its adherence to the CCSS; it is also based on a theoryof teaching math that is proven to work. That theory posits that mathematical knowledge is conveyedmost effectively when it is taught in a sequence that follows the “story” of mathematics itself. This iswhy we call the elementary portion of Eureka Math "A Story of Units." The sequencing has been joinedwith methods of instruction that have been proven to work, in this nation and abroad. These methodsdrive student understanding beyond process, to deep mastery of mathematical concepts.The goal of Eureka Math is to produce students who are not merely literate, but fluent, inmathematics. Your student has an exciting year of discovering the story of mathematics ahead!Sample Problem from Module 1:(Example taken from Module 1, Lesson 8)Kayla has 21 stickers.She gives Sergio 7 stickers.How many stickers does she have left?For more information visit

12Grade 2Module 2Eureka Math Tips for ParentsKey Words to KnowKey Words to KnowAddition andSubtraction of LengthUnitsEndpoint: Where somethingends, where measurementbeginsHash mark: The marks on aruler or other measurementtoolIn this module, we will beexploring the ruler, estimatingand measuring lengths usingvarious tools and units, andfinally, relating addition andsubtraction to length.Number Line: A line markedat evenly spaced intervalsWhat Came Before thisModule: We practicedmaking sums and differencesto the number 20What Comes After thisModule: We will begin workwith the base-10 place valuesystem How you canhelp at home: Ask questions thatencourage your studentto estimate lengths ofhousehold items Continue to reviewadding and subtractingup to 20 Practice measuringlengths longer than aruler by marking andmeasuring from a markEstimate: An approximationof the value of a quantity ornumberTape Diagram: See back ofthis sheet!Common timeterKey Common Core Standards: Relate addition andsubtraction to length Measure and estimatelengths in standardand non-standard unitsExamples:Examples:- Line A is 4 cm long, and Line Bis 7 cm long. Together, Lines Aand B measure cm.- How many centimeter cubeslong is my pencil?- In the example above, howmuch shorter is Line A than LineB?Prepared by Erin Schweng, Math Coach- How many Lego-pieces longis this bracelet?1

Eureka Math, A Story of UnitsGrade 2Module 2Spotlight on MathModels:Tape DiagramYou will often seethis mathematicalrepresentation in AStory of Units.A Story of Units has several key mathematical “models” thatwill be used throughout a student’s elementary years.The tape diagram is a powerful model that students can use to solve variouskinds of problems. In second grade, you will often see this model as an aid toaddition and subtraction problems. Tape diagrams are also called “bar models” andconsist of a simple bar drawing that students make and adjust to fit a word problem.They then use the drawing to discuss and solve the problem.As students move through the grades, tape diagrams provide an essential bridgeto algebra. Below is a sample word problem from Module 2 solved using a tapediagram to show the parts of the problem.Sample Problem from Module 2:(Example taken from Module 2, Lesson 7)Natalia, Chloe, and Lucas are makingclay snakes. Natalia’s snake is 16centimeters. Chloe’s snake is 5centimeters shorter than Natalia’s.How long is Chloe’s snake?Lucas’s snake is 3 centimeters longerthan Chloe’s snake. Who has thelongest snake: Natalia, Lucas, orChloe?For more information visit

Grade 2Module 3Place Value, Counting,and Comparison ofNumbers to 1,000In this 25-day module, students expandtheir skill with and understanding of unitby bundling ones, tens, and hundreds (upto a thousand) with straws or sticks. Theysolve simple problems that require anunderstanding of place value as a systembased on repeated groupings by 10.We are working on manydifferent ways to representtwo- and three-digitnumbers!Unit form modeled with number disks:7 hundreds 2 tens 6 ones 72 tens 6 onesWhat Came Before thisModule: We worked onmeasurement with various tools,and related our work to additionand subtraction.What Comes After thisModule: We will continue towork on adding and subtractingfluently within 100, and buildconceptual understanding upthrough 200.Ten ones are bundled into a ten.Ten bundles of ten are bundledinto a hundred.Howcanyou canHow youhelpat home:help athome:-Ask how many ones, tens,and hundreds are innumbers that you and yourstudent come across-Continue to reviewaddition and subtractionskills-Help your student beginto compare numbers byasking questions about“more than”, “less than”,and “equal”KeyVocabulary:Words to KnowKeyStandard Form: e.g. 576Expanded Form: e.g. 576 500 70 6Word Form: e.g. Fivehundred seventy-sixUnit Form: Stating theamount of hundreds, tens, andones in each number, e.g., 11is stated as 1 ten 1 one, 27 as2 tens 7 ones, 100 as 1hundred, and 576 as 5hundreds, 7 tens, 6 onesBase-Ten Numeral: The ideathat 1000 equals 10 hundreds,100 equals 10 tens, and so onBundling: Putting smallerunits together to make alarger one, e.g. putting 10tens together to make ahundredRegrouping: Renaming,(instead of “carrying” or“borrowing,”) e.g., a group of10 ones is “renamed” a tenwhen the ones are bundledand moved from the ones tothe tens placeKey Common Core Standards:Understand Place ValueMore specifically: Understand that the three digits of a three-digit numberrepresent amounts of hundreds, tens, and ones Count within 1000, skip-counting by 5s, 10s, and 100s Read and write numbers using base-ten numerals, numbernames, and expanded form Compare three-digit numbers using , , and Prepared by Erin Schweng, Math Coach1

Grade 2Module 3Eureka Math, A Story of UnitsSpotlight on MathModels:BundlingA classroom model of bundles created to show the number 476.HundredsTensOnes476 will build the foundation that enables students’ transition towriting the numerals in the place value chart.You will often seethis mathematicalrepresentation inthe lower grades inA Story of Units.A Story of Units has several key mathematical “models” thatwill be used throughout a student’s elementary years.A model used primarily in grades K-2, bundles are discrete groupings of place value units (tens,hundreds, thousands). Students or teachers easily make them by placing a rubber band or twist tiearound straws, popsicle sticks, or coffee stirrers. But these humble models are a key step in thetransition that students must make from the very concrete (seeing the bundled popsicle sticks), tothe more abstract place value chart, and finally to working with pure numbers in computation.Bundled numbers can also be “unbundled”, e.g. a group of 10 can be broken apart into itscomponent 10 ones when needed for subtraction. Students will use this same concept when theywork with division in the upper grades. Bundling and unbundling are critical skills for students tohave as a tool for our continued work with place value and operations.Module 3 Sample Problem(from Lesson 6)Timmy the monkey picked 46bananas from the tree. When hewas done, there were 50 bananasleft.How many bananas were on thetree at first?This problemwas solved usingplace valuedisks, yetanother way ofrepresentingbase-tennumerals.