John Gustafson


(630) 894-4046


Mr. John Gustafson earned his Bachelor degree in Kinesiology from the University of Illinois at Chicago.  He continued his education and received Master’s degree in Educational Leadership from Aurora University in 2006.   

Mr. Gustafson has been in education for 23 years, all of them in Keeneyville District #20.  He began his career in 1996 as the physical education teacher at Greenbrook School.  He coached boys’ basketball at Spring Wood Middle School for 8 years. He became Assistant Principal of Greenbrook School in 2007.   In 2012 Mr. Gustafson became the Principal of Greenbrook School. 

Phil Dorjath

Assistant Principal

(630) 894-4548


Mr. Phil Dorjath earned his Bachelor of Science degree in Education from Illinois State University in 2011. Go Redbirds! In 2015, he earned his first Master of Arts degree in Reading Education from Olivet Nazarene University. Mr. Dorjath continued his education and earned his second Master degree in Educational Leadership in 2019 from Concordia University.

Mr. Dorjath brings over 10 years of educational experience to Greenbrook. Prior to joining the Keeneyville family, Mr. Dorjath taught 6th, 7th and 8th grade science, social studies, reading and math at Marquardt Middle School in Glendale Heights, IL. Mr. Dorjath also served as the athletic director, coached boys basketball, girls basketball and boys volleyball during his time at Marquardt. 

Mr. Dorjath currently lives in Glen Ellyn with his wife (Brittany), their one year old son (Charlie) and their two dogs. In his free time, Mr. Dorjath enjoys relaxing with Brittany & Charlie at their family's lake house, spending time with family and friends, golfing and traveling. He is also a huge Chicago sports fan, especially baseball and football. Go Cubs & Bears!