Mandel, a Briarcliff resident who grew up in New City and later attended East Ramapo High School, announced his retirement in December at the end of the school year.
Mandel has been with Ossining since 1994 where he started as principal at Roosevelt School. He later served as principal at Brookside School and became high school principal in 1998.
"I feel it's time," Mandel said. "There are other things I want to pursue and follow-up on. I'm going to miss the people here. Hopefully, they will miss me."
At Ossining, Mandel said he has been surrounded by the best students and teachers.
"The community is very supportive," Mandel said. "I feel I lucked into this job."
During his time as principal, Madel won the GLSEN Leadership Award, the Intel Star Innovator Award and the ESSAA Administrator of the Year Award. This year, Ossining was named a School of Opportunity.
Ossining has also been lauded for its ability to shrink the achievement gap. The district doubled the percentage of minority students who graduate and narrowed test scores between student groups, according to Hechinger Report.
The school also created a bilingual program to accommodate its Hispanic student population in 2006 and the school saw state scores, college enrollment, and graduation rates for Hispanic students increase.
"Students are students," Mandel said. "Our teachers are prepared. We've had great success stories. There's always work to do and we can always accomplish more. I'm proud of the strides our district has made. Ossining High School provides opportunities for every student. We have talented teachers who our students that we never give up on them."
Ossining has also been lauded for its science research program with students being recognized by Intel and now Regeneron year after year for their research. Three Ossining students were recognized this year. Mandel has also been at the helm of an unprecedented run of success by the Ossining girl's basketball team.
"I love watching our sports teams or seeing our plays and concerts," Mandel said. "That's not even a job to me, it's so much fun. People get to see Ossining is this amazing place where a diverse group of students walk in and get a high-quality education."
In retirement, Mandel is looking forward to hiking, woodworking and sailing on the Hudson River. He said he would tell his replacement to be passionate about the job.
"Make sure to immerse yourself in the community and remember you are very lucky to have this job," Mandel said.
Mandel said his proudest moment was being able to hand his son his high school diploma. Mandel said lucky his son did not spend too much time in dad's office.
"He only came by when he needed lunch money," Mandel said.
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