Fawn is a Math Teaching and Learning Specialist at Amplify Desmos Math. She was a math coach for a K-8 school district for three years. Before that, Fawn was a middle school teacher for 30 years. Fawn was the 2014 Ventura County Teacher of the Year. In 2009, she was awarded the Math Teacher Hero from Raytheon. In 2005, she was awarded the Sarah D. Barder Fellowship from the Johns Hopkins Center for Talented Youth.

Fawn blogs about her lessons and classroom teaching at fawnnguyen.com. She also authors three other websites for teachers: visualpatterns.org, between2numbers.com, and chewablemath.com.

Fawn has been a keynote speaker and workshop facilitator at math conferences throughout the country and recently in New Zealand. She has been a part of the UC-Santa Barbara Mathematics Project Leadership team since 2005.

In 2012, she co-founded the Math Teachers' Circle in Thousand Oaks, California. Fawn served a three-year term as a committee member of NCTM's Professional Development Services Committee (PDSC) during 2015-2018.