2015 was a great year for education research. fMRI technology gave us new insight into how exercise can improve math ability by changing the structure of children's brains (#13 below). We saw how Sesame Street's 40-year history has made an impact on preparing young children for school (#7). Several studies reinforced the importance of social and emotional learning for students (#2, 5, and 9). Two must-read publications were released to help educators understand how students learn (#4 and 11). Here are 15 studies published this year that every educator should know about.

1. Well-Designed Classrooms Boost Student Learning

A classroom's physical learning space makes a difference in how well students learn. In this study of 27 schools in England, researchers found that improving a primary classroom’s physical design, including lighting, layout, and decorations, can improve academic performance by as much as 16 percent (although too many decorations can be a distraction).

Barrett, P. S., Zhang, Y., Davies, F., & Barrett, L. C. (2015). Clever Classrooms: Summary report of the HEAD project. University of Salford, Manchester.

2. The Benefits of Being Kind Last From Kindergarten to Adulthood

Kindness matters. Kindergarten students who share, help others, and show empathy are more likely to have personal, educational, and career success as adults, finds this study that tracked 753 children from 1991 to 2010.

Jones, D. E., Greenberg, M., Crowley, M. (2015). Early social-emotional functioning and public health: The relationship between kindergarten social competence and future wellness. American Journal of Public Health, e-View Ahead of Print.

3. Theatre Programs Help Students With Autism

Did you know that participating in theatre programs can help students with autism learn to play in groups, communicate with others, and recognize faces? These are the findings of a study by researchers from Vanderbilt University.

Corbett, B. A., Key, A. P., Qualls, L., Fecteau, S., Newsom, C., Coke, C., & Yoder, P. (2015). Improvement in Social Competence Using a Randomized Trial of a Theatre Intervention for Children With Autism Spectrum Disorder. Journal of Autism and Developmental Disorders, 1-15.

4. The Science of Learning

If you’re looking for an excellent review of research on how students learn, check out The Science of Learning. Drawing from cognitive science, this report breaks down the research into six principles with a full reference list and teaching tips.

Deans for Impact (2015). The Science of Learning. Austin, TX: Deans for Impact.

5. Investing $1 in Social and Emotional Learning Yields $11 in Long-Term Benefits

We know that SEL has tremendous benefits for student learning, but what are the long-term economic benefits? Researchers analyzed the economic impact of six widely-used SEL programs and found that on average, every dollar invested yields $11 in long-term benefits, ranging from reduced juvenile crime, higher lifetime earnings, and better mental and physical health.

Belfield, C., Bowden, B., Klapp, A., Levin, H., Shand, R., & Zander, S. (2015). The Economic Value of Social and Emotional Learning. New York, NY: Center for Benefit-Cost Studies in Education.

6. Low-Income Students Now a Majority

51 percent of the students across the nation’s public schools now come from low-income families.

A New Majority Research Bulletin: Low Income Students Now a Majority in the Nation's Public Schools

7. Sesame Street Boosts Learning for Preschool Children

Sesame Street was introduced over 40 years ago an educational program to help prepare children for school. Examining census data, researchers discovered that preschool-aged children in areas with better reception did better in school. Children living in poorer neighborhoods experienced the largest gains in school performance.

Kearney, M. S., & Levine, P. B. (2015). Early Childhood Education by MOOC: Lessons From Sesame Street (No. w21229). National Bureau of Economic Research.

8. Don’t Assign More Than 70 Minutes of Homework

For middle school students, assigning up to 70 minutes of daily math and science homework was beneficial, but assigning more than 90-100 minutes resulted in a decline in academic performance. Read more about the research on homework.

Fernández-Alonso, R., Suárez-Álvarez, J., & Muñiz, J. (2015). Adolescents’ Homework Performance in Mathematics and Science: Personal Factors and Teaching Practices. Journal of Educational Psychology, 107(4), 1075–1085

9. Mindfulness Exercises Boost Math Scores

Mindfulness exercises help students feel more positive, and a new study found that it can also boost math performance. Elementary school students that participated in a mindfulness program had 15 percent better math scores, in addition to several emotional and psychological benefits.

10. Boys Get Higher Math Scores When Graded by Teachers Who Know Their Names

In this Israeli study, middle and high school students were randomly assigned to be graded anonymously or by teachers who knew their names. Despite performing worse than girls in math when graded anonymously, boys had better scores when teachers knew who they were.

Lavy, V., & Sand, E. (2015). On the Origins of Gender Human Capital Gaps: Short and Long Term Consequences of Teachers’ Stereotypical Biases (No. w20909). National Bureau of Economic Research.

11. Top Psychology Principles Every Teacher Should Know

How do students think and learn? The American Psychological Association sought to answer this question with the help of experts across a wide variety of psychological fields. The result: 20 science-backed principles that explain how social and behavioral factors influence learning.

American Psychological Association, Coalition for Psychology in Schools and Education. (2015). Top 20 Principles from Psychology for PreK–12 Teaching and Learning.

12. To Help Students With ADHD Concentrate, Let Them Fidget

Since hyperactivity can be a natural state for students with ADHD, preventing them from fidgeting can hurt their ability to stay focused. For tips on how to let students fidget quietly, check out 17 Ways to Help Students With ADHD Concentrate.

Hartanto, T. A., Krafft, C. E., Iosif, A. M., & Schweitzer, J. B. (2015). A trial-by-trial analysis reveals more intense physical activity is associated with better cognitive control performance in attention-deficit/hyperactivity disorder. Child Neuropsychology, (ahead of print), 1-9.

13. The Neuroscience Behind Exercise and Math Ability

Research shows that exercise has a positive effect on learning, but studies generally tend to be observational. With the use of fMRI technology, however, researchers have gained new insight into how people learn. A team of scientists examined the brain structures of children and found that when young children exercise, their brains produce a thinner layer of cortical gray matter, which can lead to stronger math skills.

Chaddock-Heyman, L., Erickson, K. I., Kienzler, C., King, M., Pontifex, M. B., Raine, L. B., Hillman, C. H., & Kramer, A. F. (2015). The Role of Aerobic Fitness in Cortical Thickness and Mathematics Achievement in Preadolescent Children. PLOS ONE, 10(8), e0134115.

14. The Benefits of a Positive Message Home

Getting parents more involved in their child’s education is a great way to boost student learning. When teachers sent short weekly messages to parents with tips on how their kids could improve, it led to higher-quality home discussions and cut course dropout rates by almost half.

Kraft, M. A., & Rogers, T. (2015). The underutilized potential of teacher-to-parent communication: Evidence from a field experiment. Economics of Education Review, 47, 49-63.

15. When Teachers Collaborate, Math and Reading Scores Go Up

Teaching can feel like an isolating profession, but this new study shows that working in groups -- especially instructional teams -- can boost student learning.