Common Core State Standards (CCSS)
The Common Core State Standards lay out what K-12 students should know and be able to do in English Language Arts and Math. States wrote them in 2010, not the federal government. Forty-one states, DC, and Department of Defense schools still use them, sometimes under a different name. There hasn't been a national revision since 2010, so the document teachers reference today is the same one published 16 years ago.
- K-12 ELA + Math
- Released 2010
- 41 states + DC + DoDEA
- NGA + CCSSO
Reading, Writing, Speaking and Listening, and Language. Anchor standards plus grade-level standards from K through grade 12.
Eight Standards for Mathematical Practice that apply at every grade. Plus grade-by-grade content standards.
Common Core sits in two halves: ELA and Math. Each half has its own structure. ELA opens with anchor standards that describe the K-12 end goal across four strands; grade-level standards underneath each anchor spell out what that endpoint looks like at kindergarten, grade 1, grade 2, and so on.
Math is built around eight Standards for Mathematical Practice. Each K-8 grade has its own content standards grouped into domains (for example, Number and Operations in Base Ten, or Geometry). Domains break into clusters, and clusters hold the individual standards. High school math is organized by conceptual category rather than by grade, so a single Algebra standard can show up in Algebra I, Algebra II, or an integrated course.
- ELA strands (4)
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- Reading
- Writing
- Speaking and Listening
- Language
- Math practice standards (8)
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- Make sense of problems and persevere
- Reason abstractly and quantitatively
- Construct viable arguments
- Model with mathematics
- Use appropriate tools strategically
- Attend to precision
- Look for and make use of structure
- Look for and express regularity in repeated reasoning
- High school math conceptual categories (6)
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- Algebra
- Functions
- Geometry
- Number and Quantity
- Statistics and Probability
- Modeling
CCSS.MATH.CONTENT.5.NF.B.3 └──┬──┘ └─┬─┘ └─┬─┘ │ └┬┘ │ └┬┘ │ │ │ │ │ │ └── standard within cluster │ │ │ │ │ └───── cluster letter │ │ │ │ └──────── domain (NF = Number and Operations: Fractions) │ │ │ └─────────── grade level (5) │ │ └─────────────── content vs. practice │ └───────────────────── subject └─────────────────────────── framework
Read this as fifth grade, Number and Operations: Fractions, cluster B, standard 3. The standard says students interpret a fraction as the division of the numerator by the denominator.
CCSS.MATH.PRACTICE.MP3
└─┬─┘
└── practice number (1-8) MP3 is "Construct viable arguments and critique the reasoning of others." A kindergartner does it by explaining a counting strategy. A senior does it by writing a proof. The verb is the same.
CCSS.ELA-LITERACY.W.9-10.1 └──┬──┘ └────┬───┘ │ └─┬─┘ │ │ │ │ │ └── standard within strand │ │ │ └────── grade band (9-10) │ │ └────────── strand (W = Writing) │ └──────────────── content area (literacy) └────────────────────────── framework
Read this as the first writing standard for grades 9-10. The standard asks students to write arguments that support a claim with valid reasoning and strong evidence.
Common Core is a federal curriculum.
No. The Common Core is a set of standards, not a curriculum. It was written by a state-led consortium (the NGA Center and CCSSO), not by the federal government. The Every Student Succeeds Act (2015) explicitly bars the federal government from mandating, incentivizing, or even reviewing any state's standards.
Common Core dictates how I teach.
The standards say what students should be able to do by the end of the year. They do not pick textbooks. They do not set a pacing guide. They do not specify a teaching method. Those decisions sit with your district and with you.
The Math Practice Standards only apply in elementary grades.
All eight practice standards (MP1 through MP8) apply at every grade, kindergarten through grade 12. They describe habits of mathematical thinking, not grade-specific content. A high school proof and a kindergarten counting routine can both be instances of MP3.
If my state renamed Common Core, the content changed.
Most renamed versions kept the bulk of the original standards. Arizona's "Arizona's English Language Arts Standards" and Indiana's "Indiana Academic Standards" are two examples where the renaming was mostly cosmetic. A smaller number of states wrote standards that differ in real ways. The only document that legally governs what you teach is the one your state board approved.
Common Core ELA is only about literature.
The ELA standards cover four strands: Reading, Writing, Speaking and Listening, and Language. Reading informational text sits alongside reading literature at every grade. The ELA document also includes a separate set of literacy standards for reading and writing in history, social studies, science, and technical subjects for grades 6-12.
- Anchor standard
- A College and Career Readiness statement that names the K-12 endpoint for one of the four ELA strands. Grade-level standards spiral up to the anchor.
- Strand
- One of the four ELA categories: Reading, Writing, Speaking and Listening, or Language.
- Domain
- A topic area inside Common Core math (for example, Number and Operations in Base Ten, or Geometry).
- Cluster
- A small group of math standards inside a domain that share a focus. Identified by a capital letter.
- Mathematical Practice (MP)
- One of eight habits of mathematical thinking that apply at every grade. MP1 through MP8.
- Grade band
- A two-grade span (9-10 or 11-12) used in high school ELA in place of single-grade standards.
- Literacy in content areas
- A separate set of CCSS ELA standards for reading and writing in history, social studies, science, and technical subjects, grades 6-12.
- Conceptual category
- The high school math version of a domain (Algebra, Functions, Geometry, Number and Quantity, Statistics and Probability, Modeling).
- Appendix A
- The CCSS document that defines text complexity bands and the research behind the standards.
- Appendix B
- The CCSS document listing exemplar texts and sample performance tasks by grade.
- Appendix C
- The CCSS document showing annotated student writing samples at each grade.
Has Common Core been revised since 2010?
Not at the national level. The original 2010 document has not been updated. Several states have published their own revisions on top of the base standards (often small additions or wording changes). When your state board adopts a revision, that revised document is the one your district has to follow.
Why are 9-10 and 11-12 banded together?
The writers decided that high school skill growth was hard to pin to a single grade, so they grouped the standards into two-year bands. Each band describes what students should be able to do by the end of grade 10 or grade 12, not what to teach in any specific course. Schools then build their own course sequences (Algebra I, English 10, and so on) on top of the bands.
Where do the appendices fit in?
The main standards document gives the year-end goals. The appendices add the context most teachers want. Appendix A explains how text complexity is measured. Appendix B lists exemplar texts at every grade. Appendix C shows annotated student writing samples. None of the appendices are legally binding, but most curricula rely on them.
What is the difference between practice standards and content standards in math?
Content standards say what students should learn at each grade (for example, multiplying fractions in grade 5). The eight practice standards describe how students should think about math at every grade: making sense of problems, reasoning, modeling, using tools, attending to precision, and so on. A strong math lesson hits both kinds at once.
Why did some states rename Common Core?
The brand became politically toxic between 2013 and 2016. Several states (Arizona, Indiana, Oklahoma, Florida, and others) rebranded the standards under a state-specific name. In most cases the underlying content stayed close to the original, with state-specific additions on top. A handful of states wrote new standards that differ in real ways. Check your state's current document to know what is legally in force.
Does Common Core cover science or social studies?
No. Common Core only covers ELA and Math. The literacy in content areas standards inside ELA say how students should read and write in history, social studies, science, and technical subjects, but they do not cover the content of those subjects.
Are Common Core assessments still being used?
The two original test consortia (Smarter Balanced and PARCC) split after 2015. Smarter Balanced is still in use in about a dozen states. PARCC has shrunk to almost nothing as members left. Most other states now use their own state-built tests aligned to Common Core or to their state-specific successor standards.
- 1
2008: Benchmarking for Success
The National Governors Association and Achieve, Inc. publish Benchmarking for Success: Ensuring U.S. Students Receive a World-Class Education. The report argues that U.S. state standards vary too much in rigor and that high school graduates arrive at college and at work under-prepared.
- 2
2009: Common Core State Standards Initiative
The NGA Center for Best Practices and the Council of Chief State School Officers (CCSSO) convene a state-led group to write shared K-12 standards in English Language Arts and Mathematics. Forty-eight states sign on to participate. Writing teams pull from existing state standards, NCTM math standards, and college-readiness research.
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June 2010: Final standards released
The first complete Common Core State Standards are published. By the end of 2010, 36 states have adopted them. By 2013, 46 states plus DC, four territories, and DoDEA are on board.
- 4
2010-2015: Aligned assessments built
Two federally funded consortia, Smarter Balanced and PARCC, build new computer-based tests aligned to Common Core. The tests go live in spring 2015. Both consortia later shrink as states move to state-built tests.
- 5
2014-2016: Political backlash
A coordinated repeal effort runs in more than 30 states. Most attempts fail. Some succeed in renaming: Arizona, Indiana, Oklahoma, Florida, and others rebrand the standards under state-specific names, in many cases keeping most of the original content.
- 6
2015 onward: The current state
The Every Student Succeeds Act replaces No Child Left Behind. It still requires every state to keep challenging academic standards but explicitly bars the federal government from mandating any particular set. As of 2026, 41 states plus DC and DoDEA still teach Common Core, under the original name or a state-specific one.
Common Core was written to fix a specific problem. A student moving from one state to another could land in a school where "grade-level math" meant something completely different. By 2008, the National Governors Association had documented that fewer than half of U.S. high school graduates were ready for college-level coursework. State standards varied widely in rigor, and college placement tests rarely lined up with K-12 exit standards. The 2009 initiative tried to anchor every state to one shared definition of what a student at each grade should be able to do.
Adoption moved fast, then got political. In 2010 and 2011, states signed on quickly, in part to qualify for federal Race to the Top funding. By 2013, state legislatures and parent groups had started pushing back on the content and the speed of the rollout. Most repeal bills failed. A few succeeded in renaming the standards. Even fewer succeeded in writing genuinely new ones from scratch. The 2010 architecture survived almost everywhere: the anchor standards in ELA and the eight mathematical practices that sit alongside the content. As of 2026, 41 states plus DC and DoDEA still teach what is recognizably the same document, even where the Common Core label was retired.
- Publisher
- NGA Center for Best Practices and the Council of Chief State School Officers (CCSSO).
- First released
- June 2010.
- Current version
- 2010. No national revision since release. Some states have published their own revisions on top of the base.
- Subjects covered
- English Language Arts and Literacy in History/Social Studies, Science, and Technical Subjects; Mathematics.
- Grade range
- K-12. Grade-by-grade for kindergarten through grade 8. Two-year bands for grades 9-10 and 11-12.
- Adoption
- 41 states, the District of Columbia, and the DoD Education Activity, as of 2026.
- Legal status
- Voluntary state adoption. The Every Student Succeeds Act (2015) explicitly bars the federal government from mandating, incentivizing, or reviewing any state's standards.
- Companion documents
- Appendix A (text complexity research and bands), Appendix B (exemplar texts and sample tasks), Appendix C (annotated student writing samples). None are legally binding.