My research explores how teachers develop mathematical proficiency for teaching from professional experiences (i.e., in preparation programs, with colleagues in schools, and in professional development). I define mathematical proficiency for teaching to include both knowledge and dispositions (cognitive and noncognitive skills) and hypothesize that these components interact and develop together. Teachers are increasingly seen as the key to improving educational quality, yet little is known about how they learn the knowledge they use in their work or about the role of teachers’ dispositions in learning or using this knowledge. My approach to the problem has been influenced by recent work identifying and measuring the mathematical knowledge that teachers use in practice, by theories of motivation that link knowledge use and acquisition to social contexts, and by the power of quantitative methods to describe educational phenomena at scale.  Ph.D. Mathematics Education, 2013, University of Georgia, Athens, GA
 M.A. Mathematics, 2011, University of Georgia, Athens, GA
 B.A. Mathematics, 2004, Dartmouth College, Hanover, NH
AWARDS  AERA Dissertation Grant awardee.
 Jacobson, E., Creager, M., Ayedeniz, F. (2015). Maintaining quantitative coherence: Preservice elementary teachers explanations using concrete representations. In Bartell, T. G., Bieda, K. N., Putnam, R. T., Bradfield, K., Dominguez, H. (Eds.). (2015). Proceedings of the 37th annual meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education, p. 904907. East Lansing, MI: Michigan State University.
 Nazarewicz,P., OKelley, S., Jacobson, E., Blume, G., Heid, M. K. (In press). Constructing a tangent line,In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Jacobson, E. (2014). Using covariation reasoning to support mathematical modeling. Mathematics Teacher, 107 (7), 515519.
 Shimizu, J., Donaldson, S., Edenfield, K., Jacobson, E. (In press). Quadratic equations. In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Tillema, E., Johnson, H., OKelley, S., Jacobson, E., Blume, G., Heid, M. K. (In press). Connecting factoring with the quadratic formula. In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Jacobson, E. (2014). Developing knowledge for teaching from experience: Mathematics teaching and professional development in the United States of America. In J. Orchard and V. Ellis (Eds.) Learning teaching from experience: Multiple perspectives, international contexts, pp. 225240. London, UK: Bloomsbury.
 de Araujo, Z., Jacobson, E., Singletary, L., Wilson, P., Lowe, L. and Marshall, A. M. (2013), Teachers conceptions of integrated mathematics curricula. School Science and Mathematics, 113,285296. doi:10.1111/ssm.12028
 Jacobson, E. Izsk, A. (2015). Knowledge and motivation as mediators in mathematics teaching practice: The case of drawn models for fraction arithmetic. Journal of Mathematics Teacher Education, 18, 467488.
 Izsak, A., Jacobson, E., de Araujo, Z., Orrill, C. H. (2012) Measuring mathematical knowledge for teaching fractions with drawn quantities. Journal for Research in Mathematics Education, 43(4), 391427.
 Johnson, H., Karunakaran, S., McClintock, E., Nazarewicz, P., Jacobson, E., Edenfield, K. (In press). Absolute value and square root. In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Bradshaw, L. P., Izsak, A., Templin, J., Jacobson, E. (2014). Diagnosing teachers understandings of rational number: Building a multidimensional test within the diagnostic classification framework. Educational Measurement: Issues and Practice. 33(1), pp. 214 DOI:10.1111/emip.12020
 Allen, R., OKelley, S., Jacobson, E.(In press). Trigonometric identities In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Jacobson, E (2014). The Nature and Growth of Mathematical Proficiency for Teaching in Schools and Districts in Georgia. Research report.
 Jacobson, E. Izsak, A. (2014). Using coordination classes to analyze preservice middlegrades teachers difficulties in determining direct proportion relationships. In J. Lo, K. R. Leatham, L. R. Van Zoest (Eds.), Research Trends in Mathematics Teacher Education, pp. 4765. New York, NY: Springer.
 Jacobson, E. Kilpatrick, A. (2015). Understanding teacher affect, knowledge, and instruction over time: an agenda for research on productive disposition for teaching mathematics. Journal of Mathematics Teacher Education, 18, 401406. DOI 10.1007/s1085701593169.
 Reed, S., Conner, A., Donaldson, S., DuCloux, K., Edenfield, K., Jacobson, E. (In press). Absolute value equations and inequalities. In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Johnson, H., Reed, S., McClintock, E., Jacobson, E. Edenfield, K. (In press). The product rule for differentiation. In M. K. Heid, P. S. Wilson, G. W. Blume (Eds.) Mathematical understanding for secondary teaching: A framework and classroombased situations, Information Age.
 Decomposing and Rehearsing Explanations of Algorithms in Mathematics (DREAM): Investigating OnlineMediated Learning for Teacher Education
 Izsak, I. Jacobson, E. (2014). Relationships between teacher characteristics and knowledge profiles for fractions. Paper presented at the Joint Meeting of PME 38 and PMENA 36: Vancouver, Canada.
 Jacobson, E. (April, 2014). The Effects of the Timing, Duration, and Quality of Teaching Practice on K6 Mathematics Teachers Content Knowledge for Teaching. Poster presented at the annual meeting of the American Educational Research Association: Philadelphia, PA.
 Jacobson, E. Remillard, J. (April, 2014). The Emergent Relationship between Item Design and Construct Development in the Cycle of Discovery, Innovation, and Application. Paper presented at the annual National Council of Mathematics Teachers Research Presession: New Orleans, LA.
 Jacobson, E., Creager, M., Ayedniz, F. (2015, March). Maintaining Quantitative Coherence: Preservice Elementary Teachers Explanations Using Concrete Representation. Talk presented at Indiana Mathematics Education Research Symposium, Indiana University Purdue University, Indianapolis, IN.
 Jacobson, E. (Sept. 2014). Teaching Practice and K6 Mathematics Teachers Knowledge and Belief. Paper presented at the Fall Research Conference of the American Educational Research Association, Washington, D.C.
 Jacobson, E. (2014). The role of experience in the development of mathematical knowledge for teaching. Paper presented at the Joint Meeting of PME 38 and PMENA 36: Vancouver, Canada.
 Journal for Research in Mathematics Education: Reviewed manuscript submissions.
 International Group for the Psychology of Mathematics Education (PME): Reviewed conference paper submissions.
 The Mathematics Teacher: Reviewed manuscript submissions for the practitioner journal, the Mathematics Teacher.
 Journal of Teacher Education: Reviewed manuscript submissions.
