Educational:

• "How much do you bid?"
• Splash 2009 (run by MIT's Educational Studies Program), November 11, 2009.
• Guest lecture, The Math Circle, May 3, 2009.
• "Why matchmakers?"
• Tea and Math (at MIT's Random Hall), April 18, 2009.
• Spark 2009 (run by MIT's Educational Studies Program), March 7, 2009.
• Guest lecture, The Math Circle, December 7, 2008.
• "Microeconomics in 50 Minutes"
• Splash 2009 (run by MIT's Educational Studies Program), November 11, 2009.
• Spark 2009 (run by MIT's Educational Studies Program), March 7, 2009.
• "Quadratic Form Representation Theory in One Hour"
• Guest lecture, The Math Circle, October 21, 2007.

At the Harvard Math Table:

	"The Rap Battle of the Millennium", May 5, 2009: Zachary Abel and I rap our way through the seven Clay Mathematics Institute Millennium Prize Problems in the first-ever "sung through" math table lecture.
	"Koch's Condition on Type II Codes of Length 24", April 14, 2009: An introduction to binary linear codes and harmonic weight enumerators, with an application to a theorem of Koch on the possible tetrad systems of Type II codes of length 24.
	"Who wants to be a Math Concentrator?", March 17, 2009: A panel of current mathematics concentrators advising prospective concentrators in mathematics and related fields.
	"Matchmaker, Matchmaker, Clear Out My House", November 11, 2008: A thirty-minute course in the theory of matching, introducing the marriage and college admissions problems, the Gale-Shapley algorithm, unraveling, and generalized matching.
	"C=15", October 30, 2007 (awarded the top Robert Fletcher Rogers Prize): A discussion of recent results in quadratic form representation theory, focusing on the Conway-Schneeberger "Fifteen Theorem," the Bhargava-Hanke "290 Theorem," and Kim, Kim, and Oh's criterion results for representations of higher-rank forms.
	"Opetopia", November 21, 2006: An introduction to the theory and applications of $n$-categories, focusing especially on the "opetopic" realization of $n$-category theory.
	"Metric-Preserving Functions", February 21, 2006: An introduction to the theory of metric-preserving functions, those functions $f:[0,\infty)\to[0,\infty)$ such that for any metric space $X$ with metric $d$, $f\circ d$ is a metric on $X$.

On The Harvard College Mathematics Review:

• "The Harvard College Mathematics Review"
• Northeastern Section of the Mathematical Association of America Fall 2007 Meeting, November 16, 2007.

Panel Presentations:

• "Economics Graduate School Panel"
• Harvard Undergraduate Economics Association, October 26, 2009.
• "What Helps Students Learn: A Discussion with Undergraduates"
• Derek Bok Center Fall Teaching Conference, August 28, 2009.
• "Summer and International Opportunities"
• Harvard Alumni Association Meeting, February 1, 2008.
• "The Winning PRISE Experience"
• Harvard Alumni Association Meeting, February 1, 2007.