2nd Grade Math: Unit 3
October 12 and October 26, 2017 /Subtraction Up To 1,200
Disregard the word 'borrow' in the video instead we use the term regroup.... 'borrowing' misrepresents what is taking place.
I have included this mat in your small group folder
Regrouping ones and tens work mat
2.2 Number and operations. The student applies mathematical process standards to understand how to represent and compare whole numbers, the relative position and magnitude of whole numbers, and relationships within the numeration system related to place value.
2.4B add up to four two digit numbers using mental math strategies based on knowledge of place value.
2.4C solve one step and multi step word problems involving addition within 1,200.
2.4D generate and solve problem situations for a given mathematical sentence involving addition.-Math Journals Write a math story for 126+83=
Do you want to create and keep your sentence stems for future lessons/years then use this resource! It is a resource I have used for many years as an interventionist and just remembered recently to revisit, it’s called senteacher.com. You will be able to create sentence stems and vocabulary words you can then copy on card stock and laminate if you wish for years of use. You can make large sentence stems or smaller ones it’s up to you..if you want you can punch holes and keep then in a ring per unit for students to access as well when working independently or with a partner. Come by my room if you want to see some samples….:)
place value, chart, part, number sentence, equation, algorithm, equals,subtract, whole, minus, is the same as, relationship, difference
Mrs. Ochoa's class has 337 Dream Box points. Mrs. Sander’s class has 179 less points than Mrs. Ochoa’s class. How many Dreambox points does Mrs. Sander's have?
Represent the number sentence using the place value names-PVC CHART
Represent the whole number using pictures (models) VM, base ten blocks and PV chart:
Connect to a Visual Model/Number Bond/Part-Part/Whole/then transition to number sentence :
Reinforce vocabulary-label and discussions
Use terms: regroup ....not borrow...
Place Value Charts/Mats
Base Ten Blocks
Math Journal/Recording sheet( min. twice a week)
Focus: Expose your students to at least TWO different methods for subtraction
Number Line, Place Value Chart, OR Traditional Algorithm w/pictorial
The goal is to to allow students to develop a deeper understanding of the concept.
Discussion, Turn and Talk, journal/recording sheet entries..
Think Central Manipulatives
Glencoe Virtual Manipulatives
Break a Hundred (MIF Book)-Lesson Three-Subtraction with Regrouping Ones and Tens
Lesson One: Subtraction without Regrouping
Ask questions: What do we know about the story? (some fish are orange, some are not...)
Reveal the numbers..
As questions: What do we know? ( We know how many fish are in the pond and how many are orange) How many are orange? What are some colors the other fish could be? (red, blue. black,etc) How can we find how many are not orange?
Subtract, take away, less ____
Write the title' Subtraction without Regrouping'
Create anchor chart/SB copy with students, anchor chart should include:
- Place Value Chart-Students share how to make the chart
- Pictorial-students volunteers can come up and draw the base tens/Virtual maipulatives, Base Ten Blocks
- Number sentence/Number Bond/Bar Model-at least one or all three
- vocabulary words-label
- Solution statement-students turn and talk and share the statement.