Directors and Staff

Ms. O’Riordan has served as a music teacher at North High School since 2007.  As a National Board Certified Teacher, she has worked with her colleagues to build and refine a choir program that includes four curricular choirs, three auditioned ensembles, and the All Access Choir, a group where general education and students with special needs work side-by-side. ​Ms. O'Riordan teaches Freshman Choir, Concert Choir, Treble Choir, A Cappella Choir,  Concert Singers and All Access Choir.  In addition to teaching choral classes, Ms. O'Riordan instructs two levels of guitar class.

A native of Naperville, Ms. O'Riordan ventured off to NY to pursue higher education. She earned a Bachelor of Music Degree in Voice Performance with an Arts Leadership Certificate from the Eastman School of Music in Rochester, NY. Ms. O'Riordan continued on at Eastman to earn a Master of Music Degree in Music Education (Choral/Vocal Emphasis). She is an active member of the American Choral Directors Association and the Illinois Music Education Association, where she has served as a District 1 Choral Representative. In addition to her teaching, she has worked as a soloist and has sung with professional choirs in the Chicago area.

Ms. O'Riordan is committed to helping students achieve excellence and to the development of students as musicians and as people. She enjoys the opportunity to celebrate the power of shared musical performance.​ She lives in Naperville with her husband and two children. In her free time, Ms. O'Riordan enjoys watching movies, going to concerts, reading, and watching her kids perform in both music and sports.

​Dr. Piekarz is a proud alumnus of Downers Grove South High School who returned to District 99 as a faculty member in 1996.  Within the Fine Arts Department, he serves as a Director of Choirs (co-teaching the Concert Choir & A Cappella Choir with Mrs. O'Riordan, as well as directing both the Treble Ensemble & Chamber Choir), and this year is also teaching the Jazz Workshop Band.  Additionally at DGN, he works within the Career & Technical Education (CTE) department, where he has served as the coordinator of the Introduction to Teaching program for over ten years.

Dr. Piekarz earned a Bachelor of Science in Music Education (Vocal/Choral Emphasis) from the University of Illinois in 1994, and went on to receive a Master of Music Degree (Music Education Emphasis) from Northern Illinois University in 1999. He has a Doctor of Education (Ed.D.) in Curriculum Leadership from Northern Illinois University, which he earned in 2006.

Additionally, Dr. Piekarz currently serves the Illinois Music Education Association (ILMEA) on the Board of Directors as the Chorus Division President.  He is an active choral middle school and high school choral clinician in Chicagoland, and he teaches collegiate courses in music education when the opportunity and his schedule allows.

Dr. Piekarz and his wife live in Lisle.  They have three really cool adult children, and two silly dogs.

Ms. Valerie Lorimer is the Collaborative Pianist for the Fine Arts Department. She earned a Bachelor of Music from Michigan State University and a Master of Music from Northwestern University. Ms. Lorimer played professionally in the Chicagoland area primarily for choirs and vocalists, at Chicago Opera Theater, the Ravinia Festival Chorus, and the Chicago Symphony Orchestra Chorus. She had the pleasure of playing one of Sir Georg Solti’s last rehearsals with the chorus on the CSO stage. 

Ms. Lorimer taught piano privately for many years and is also a composer. Her compositions have been performed in the United States and Europe. When not tickling the ivories, Ms. Lorimer loves creating art, reading and traveling.