Board & Staff

Executive Director


Sarena Lawrence first became involved in El Sistema in 2013 when her daughter joined the orchestra. After seeing the powerful impact music instruction can have on youth, she began supporting the program by developing fundraising opportunities for the families. She has since applied her experience running organizations dedicated to youth development by becoming El Sistema’s Assistant Director in 2015. In 2019 Sarena became the Executive Director of El Sistema and continues to see each student grow throughout the years. Sarena grew up and continues to live in Waukesha with her husband and two wonderful children.


String Instructors


Andrea Buchta

Violinist and Waukesha native Andrea Buchta has taught for around 20 years in southeastern Wisconsin.  She has directed string programs in both public and private schools and has maintained for 18 years (and currently teaches) a private violin and viola studio of young beginner through advanced high school students in Brookfield, WI.  Many of her private students are strong members of the Milwaukee Youth Symphony Orchestra and their school orchestras.

Andrea holds a BA in Music Education from Wisconsin Lutheran College and a MM in String Pedagogy from the University of Wisconsin-Milwaukee.  She has completed short term teacher training courses, pre-twinkle – Suzuki book 8, at the American Suzuki Institute, Stevens Point.  Her main teachers include Eriks Klavins, former principal second violinist of the MSO, and Bernard Zinck, violin professor at the University of Wisconsin-Milwaukee.

In addition to teaching, Andrea also performs professionally in several area orchestras and as a freelance violinist.  She can be seen performing in the Wisconsin Philharmonic, Racine, Festival City, Kenosha and Fox Valley Symphonies.  When not teaching, performing, or practicing, Andrea enjoys being active outdoors and traveling when able to with friends and family.


Heather Weber – Violin, Viola, Cello

Heather began her journey with El Sistema over 6 years ago when her youngest son joined the program in first grade. Initially a volunteer, Heather joined the GMES staff that same year and has been teaching Violin, Viola and Cello with us ever since. Heather is currently the Montessori Music Specialist at Adeline Montessori School in Waukesha. She was previously Music Specialist at Montessori School of Waukesha, where she also taught strings and Lower Elementary.

Heather served 4 years in the US Air Force, where she played snare drum in the Drum and Bugle Flight, and later served as a Cryptological Linguist during Operation Desert Storm.  She earned her BA from Marquette University in Criminology and Law Studies with a Minor in Biology, then attended Marquette University Law School. After her 5th child attended a Montessori School, she knew that teaching was her calling and she enrolled in the Master of Arts in Montessori Education program at UW River Falls.

Heather has played violin for over forty years. She has studied at the Wisconsin Conservatory of Music and attended Suzuki Violin and Early Childhood training at the American Suzuki Institute, Stevens Point, WI.  A native of Wisconsin’s north woods, Heather currently lives in Waukesha with her two youngest children.


Wendy Muller – Cello, Violin 

Wendy is an instrumental musician and singer. She began with El Sistema in 2023 working with beginner violinists. She has been playing cello for 6 years. Wendy studied music education at Northern Illinois University but graduated from UW Whitewater with a degree in Elementary Education. When she moved to Waukesha, she joined the Waukesha Choral Union and sang in the Sound of Music at First Stage in Milwaukee. She continues as a musician in the community in choirs and performing at church.


Casey Arnold – Violin, Viola, Cello

Casey is a talented instrumental musician and singer.  Casey began her work with El Sistema in 2015 as a volunteer.  In 2016 Casey was invited to be a teaching assistant and co-taught the Summer Community Connections Program.  Casey is a loved and respected teacher with our students.  She continues her work as a musician in the community in choirs and performing at weddings.


Abby Kelly

Abigail Kelly is a recent graduate of Carroll University, where she received a BA in violin performance. Abigail is passionate about music education, and has been teaching violin lessons for over five years. She has participated in many orchestras including Grace Notes Orchestra, Waukesha Area Chamber Orchestra, and Carroll University Chamber Orchestra. In addition, she is currently an active freelancer in the Southeast Wisconsin region.



Erika Lawrence – Waukesha South High School (2019)

Alex Richards – Waukesha West High School (2020)

Lipika Veluri – Waukesha South High School (2021)

Alisha Agenten – Waukesha South High School (2022)


Job Opportunities



Board of Directors

Abby Lorenz, President
Susan Mingesz, Vice President
Susan Goldstone, Treasurer
Lori Roth, Secretary
Kristin Agenten
Debbie Bayee
Jean Ericson
Karen Patrick
Jose Sanchez