Education Standards
OREGON MATH STANDARDS (2021): [K.NBT]
Overview
The intent of clarifying statements is to provide additional guidance for educators to communicate the intent of the standard to support the future development of curricular resources and assessments aligned to the 2021 math standards.
Clarifying statements can be in the form of succinct sentences or paragraphs that attend to one of four types of clarifications: (1) Student Experiences; (2) Examples; (3) Boundaries; and (4) Connection to Math Practices.
2021 Oregon Math Guidance: K.NBT.A.1
Cluster: K.NBT.A - Work with numbers 11-19 to gain foundations for place value.
STANDARD: K.NBT.A.1
Standards Statement (2021):
Compose and decompose from 11 to 19 into groups of ten ones and some further ones using objects, drawings, or equations.
Connections:
Preceding Pathway Content (2021) | Subsequent Pathway Content (2021) | Cross Domain Connections (2021) | Common Core (CCSS) (2010) |
N/A | 1.NBT.B.2 | K.OA.A.2, K.OA.A.3 | K.NBT.A.1 K.NBT.A Crosswalk |
Standards Guidance:
Clarifications
- Students should be able to put together (compose) and break apart (decompose) numbers into a group of ten ones and some further ones to understand that these numbers are composed of ten ones and one, two, three, four, five, six, seven, eight, or nine ones.
- Students should use strategic thinking in order to communicate quantities for authentic purposes.
Terminology
- Composition refers to putting numbers together, such as 10 + 2 = 12
- Decomposition refers to breaking multi-digit numbers apart, which would be into groups of tens and ones at this grade level, such as 14 = 10 + 4.
- Math drawings are simple drawings that make essential mathematical features and relationships salient while suppressing details that are not relevant ot the mathematical ideas.
Teaching Strategies
- Compose and decompose numbers from 11 to 19 into ten and single ones (not “a ten;” this is in first grade).
- Use objects or drawings to record each composition or decomposition. An example would be a student recognizing that the number 13 is made up of ten single ones and three more. This is specific to teen numbers only.
- Students should be given the opportunity to use five frames, ten frames, and rekenreks with support to demonstrate each composition or decomposition.
Progressions
- The numerals 11, 12, 13, ..., 19 need special attention for children to understand them. The first nine numerals 1, 2, 3, ..., 9, and 0 are essentially arbitrary marks. These same marks are used again to represent larger numbers. Children need to learn the differences in the ways these marks are used. For example, initially, a numeral such as 16 looks like "one, six," not "1 ten and 6 ones." Layered place value cards can help children see the 0 "hiding" under the ones place and that the 1 in the tens place really is 10 (ten ones). (Please reference page 5 in the Progression document).
Examples
- Illustrative Mathematics: [What Makes a Teen Number?]
- Student Acheivement Partners: [Counters & Ten Frame]