Understand that the two digits of a two-digit number represent amounts of tens and ones.
Unitize by making a ten from a collection of ten ones.
Model the numbers from 11 to 19 as composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones.
Demonstrate that the numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight, or nine tens, with 0 ones.
Step 1: Lesson Standards & Learning Goals
The focus of this standard is for students to demonstrate understanding of place value concepts with all 2-digit numbers up to 99.
Unitize by making a ten from a collection of 10 ones:
Unitizing is a sophisticated concept where students are able to recognize, represent, and explain that 10 ones can be represented by a group of 10 using concrete materials or drawings on a ten frame, which students began in kindergarten (NC.K.NBT.1).
In first grade, students are asked to start to group those ten individual ones as a whole unit: “one ten.” This is known as unitizing.
When students unitize, they are able to count groups as though they were individual objects. For example, 4 trains of ten cubes each have a value of 10 and would be counted as 40 ones or as 4 tens. It can often be challenging for students to consider a group of something as “one” when previous experiences have been counting single objects. This is the foundation of the place value system and requires time and rich experiences with concrete manipulatives to develop.
Note: Pre-grouped materials (e.g., materials like place value base ten blocks and bean sticks, which must be traded to make a ten) should not be introduced until a student has a firm understanding of composing and decomposing ten. Additionally, students should only use proportional manipulatives for place-value work, such as 10 snap cubes or a base ten rod, that have a “ten” that is ten times bigger than the "one."
Model the numbers 11 to 19:
This aspect of the standard should be integrated throughout the year, building on the work from kindergarten (NC.K.NBT.1).
Demonstrate that multiples of ten refer to a group of tens with 0 ones: (2nd Quarter)
This aspect of the standard expects students to create a representation of a multiple of 10 (between 10 and 90) and explain the idea that these numbers contain groups of 10 and no additional ones. Students should also have ample experience building 2-digit numbers with concrete models and drawings AND represent the number in expanded form, which is an addition equation that shows the tens and ones (e.g. 75 = 70 + 5). Expanded form is a foundational application of place value and in Grade 1 should always be joined with a representation with concrete models such as place value (base ten) blocks or drawings of place value blocks.
How can I demonstrate understanding of place value concepts with 2-digit numbers?
What are two-digit numbers?
How are models used to represent two-digit numbers?
collection
compose
digit
group
number
model
ones
place value
tens
two-digit number
unitize
Unitize (combine, group) by making a ten from ten ones.
Use manipulatives to build sets of tens.
Model the numbers from 11 to 19 as a ten and a number of ones.
Use manipulatives to build sets of tens with "leftovers" to represent ones.
Demonstrate that the numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to a number of tens, with 0 ones. (2nd Quarter)
Use bundles of 10 to represent decade numbers.
Explain the idea that these numbers contain groups of tens and no additional ones.
Numbers greater than 10 can be represented as groups of tens and ones.
The numbers from 11 to 19 are composed of a ten and one, two,…or nine ones.
The numbers 10, 20,…90 refer to one, two or nine tens (and 0 ones). These are also referred to as decade numbers.
Our number system uses the digits 0 - 9 and place value to build all of our numbers.
When objects are grouped into sets of ten, the "leftovers" are ones.
Ten can be thought of as a set or bundle of ten ones.
Step 2: Assessment
NCDPI Math Assessment Released Forms
Grade 1 Math Assessment Practice Prompts
Grade 1 Released Summative Assessments
Step 3: Lesson Instructions
Read aloud
Counting by 10
Read aloud
Making groups of 10 with leftovers
Exploration
Use manipulatives to create the number 17
Number Talk
What is the value of the one in the number 17? What is the value of the 7 in 17?
https://missgiraffesclass.blogspot.com/2014/08/place-value-moving-and-new-blog-design.html
Tools 4 NC Teachers
Math Expressions - (Barnes and Hearne) - Standards Alignment
Motivation Math
Think Up! Math
Khan Academy - 1st Grade Math
Eureka Math/Engage NY Free Resources
Embarc Online (Eureka Math)
Zearn Math - Online Support Practice for Eureka Math (Requires free account)
North Carolina Collaborative for Mathematics Learning - Grade 1 Instructional Framework
NCDPI Resources
Grade 1 Math Assessment Practice Prompts
