The What Works Clearinghouse (WWC) was established in 2002 by the Institute of Education Sciences at the U.S. Department of Education to provide educators, policymakers, researchers, and the public with a central and trusted source of scientific evidence about "what works" in education. Mathematica Policy Research, Inc., administers the WWC under contract to the Department.

The need to ensure that all students and schools meet high standards has increased the demand for evidence of what works in education. Currently, few resources help education decision makers differentiate high-quality research from weaker research and promotional claims. The WWC provides educators with credible and reliable evidence that they can use to make informed decisions.

A "topic" is defined by its intended outcome (such as improving reading skills, improving math skills, or reducing the dropout rate), the intended population (such as elementary school students), and the types of interventions (programs, products, practices, or policies) that may improve outcomes for students.

"Interventions" are programs (such as whole school reform), products (such as a textbook or curriculum), practices (such as mixed-age grouping), or policies (such as class size reduction).

The WWC has reviewed research on seven topics: Beginning Reading, Character Education, Dropout Prevention, Early Childhood Education, Elementary School Math, English Language Learners, and Middle School Math Curricula. Indicated below is the status of these topic areas. Active topics are those with studies currently being reviewed by our researchers and evaluators. Inactive topics may be revisited periodically in future years.

1. Beginning Reading Interventions (Active)
   Reading interventions for students in grades K-3 (or ages 5-8) that are intended to increase skills in alphabetics (phonemic awareness, phonological awareness, print awareness, and phonics), reading fluency, comprehension (vocabulary and reading comprehension), or general reading achievement.
   
   
2. Early Childhood Education Interventions (Active)
   Curricula and practices designed for use in center-based settings with 3- to 5-year-old children who are not yet in kindergarten, with a primary focus on cognitive and language competencies associated with school readiness (language, literacy, math, and cognition).
   


3. Elementary School Math Interventions (Active)
   Math interventions that focus on math curricula for students in grades K-5 and are designed to increase student outcomes related to mathematics achievement.
   
   
4. Middle School Math Interventions (Active)
   Curriculum-based interventions outlining the fundamentals of mathematics that students should know and be able to do, including instructional programs, materials that organize the mathematical content, and assessments.



5. Dropout Prevention Interventions (Inactive)
   Interventions designed for middle school, junior high school, or high school that aim to increase high school completion.
   
   
6. English Language Learners Interventions (Inactive)
   Curriculum-based interventions designed to improve the English language literacy or academic achievement of elementary school students who are English Language Learners.



7. Character Education Interventions (Inactive)
   Interventions that focus on developing character traits and providing comprehensive character education.

If you would like to nominate a topic for review, go to Research to Review. If you would like to nominate a study on a particular intervention for consideration, visit Research to Review.

The WWC uses evidence standards to assess the strengths and weaknesses of a study's methodology, such as (1) the type of design it uses (for example, a randomized controlled trial or a quasi-experimental design), (2) the strength of the study's data (the types of outcomes it measures, the response rates for its data collection efforts), and (3) the adequacy of the study's statistical procedures (for example, whether sampling variance is estimated appropriately and whether results of key statistical tests are verifiable). Click here to see the standards.

Each WWC topic is reviewed by a team composed of a principal investigator and a group of reviewers. The team develops a protocol that defines the scope of the review and how the standards will be applied to the evidence. After a review topic is identified, the team conducts a thorough search of published and unpublished research literature to gather relevant studies. The search is supplemented by submissions from intervention developers and the public. The team reviews the relevant studies using the WWC Evidence Standards, and prepares intervention reports based on the studies that meet the standards.

The WWC assesses evidence on the effectiveness of educational interventions. It does not endorse interventions. A WWC rating of "positive" for an intervention, for example, means there are at least two studies of the intervention that met evidence standards, and the studies found positive effects on student outcomes. It does not mean that the WWC recommends that users should implement that intervention or encourages them to do so. Many other factors need to be considered to identify an appropriate intervention to implement.

The Registry of Outcome Evaluators is an online database of evaluators (individuals and organizations) who conduct research on the effects of educational interventions. The entries include contact information, resumes, and samples of relevant reports and peer-reviewed journal articles. Users can generate reports of evaluators who have experience working in particular content areas or geographic regions, or with particular types of student populations. They can also search for evaluators by name or organization. To search the Registry of Outcome Evaluators, click here.

The WWC website provides registration forms for individual and organizational evaluators to use to submit the information required for inclusion in the Registry of Outcome Evaluators. Users can register at any time. To learn more about the registry, or to search the database, click here.