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Bishop Mcgann-Mercy Diocesan High School

Private | 7-12 | 537 students


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Living in Riverhead

Situated in a suburban neighborhood. The median home value is $265,000. The average monthly rent for a 2 bedroom apartment is $1,490.

Source: Sperling's Best Places
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4 stars

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18 reviews of this school

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Posted September 28, 2014

Unfortunately, this school should not call itself a catholic school. I've never in my life have seen educators want the students to fail as much as this staff!! Instead of working with their students to succeed they would rather fail them. As far as the administration, they pick and choose who they want to discipline. If it's an easy target they will step in but if it's a big donors child they do nothing. It's a shame how this school is considered a catholic school but there is nothing Christian about it!
—Submitted by a parent

Posted March 1, 2014

My son loves Mercy! Thank God for Catholic School. When he attended Pulaski he was almost killed by a student, Riverhead public schools, pure violence. My son has been at Mercy since 7th grade, he is now a 9th grader, and honor student. He has good friends there, they are not snobby, and we are not rich, not even close. My priorities are not fancy cars, clothes, and having my hair and nails done. My priority is an excellent education and safety for my son. After my son was in the dangerous Riverhead public school, the only option was Mercy or home school. I chose Mercy instead of home schooling for so many positive reasons for my son. He couldn't be happier. Way to go Mercy!!!
—Submitted by a parent

Posted November 23, 2013

I went to the school play here just this weekend and was absolutely DISGUSTED to hear foul language used in the play repeatedly, in addtion to using the Lord's name in vain and two male characters kiss on the stage. Unbelievable. I wonder how the priests in the audience and the school principal feel about it. Apparently there are no differences between this parochial school and the local high school.

Posted October 20, 2013

As a prior student I have to say these were some of the best four years of my life. I still have great friends and close relationships with the people I met here at mercy. The faculty truly believes in you and wants the best out of you. Yes they do push you and they don't except less than your full potential but that is one of the best qualities of this special place. Unlike other catholic schools on Long Island, mercy has the heart and character. In other words the morals and values you learn here are truly priceless. You cannot put a price tag on friendships, right from wrong, compassion, selflessness, and the meaning of the word family. This is all a result of being a part of the mercy family . I wouldn't trade it for the world

Posted January 9, 2011

I love Mercy and I think all the kids I know are really nice. I'm a new eighth grader and I'm shy. I was afraid everyone would be cliquey and have friends already and would ignore me, but everyone was kind and accepting. there were only a few annoying kids. Overall, it's great.

Posted August 20, 2010

The school is centered around family and values where all are respected. Parents have like kind values and education is a top priority. All the children are involved in activities there is something for everyone there. Go Monarchs
—Submitted by a parent

Posted February 7, 2010

Best school ever! great teachers and faculty members. It's like my second family/home.
—Submitted by a student

Posted February 7, 2010

Best school ever! great teachers and faculty members. It's like my second family/home.
—Submitted by a student

Posted October 13, 2009

I am a freshman at McGann Mercy and I agree with the girl in 7th grade, it is very cliquey and the kids there are very stuck up. Honestly i hate it there. Compared to my firends in public school the kids are pretty mean. The academics are okay but nothing great. I also hope to switch back to public school.
—Submitted by a student

Posted June 30, 2009

I am a 7th grader here at McGann-Mercy. The acedemics are good, but the classes are really small and form cliques. The kids seem stuck up,coming from public school the kids weren't as spoiled. I grew tired over this school very quickly and now i'm hoping to go back to public school for my 8th grade year.
—Submitted by a student

Posted December 20, 2008

I am a freshman and I love Mc Gann Mercy. The staff is wondeful and the principal is the nicest man! Phone calls to home wishing a merry christmas and other school related things are really a plus! The 'friendly neighborhood chaplain' Father Mike is a real character! In the best way! I just love everything about the school and I'm so glad my parents send me there! =]
—Submitted by a student

Posted December 18, 2008

Bishop McGann has seen great strides in thier academics, Athletics, and Spiritual guidance. Dr. Steve Cheeseman has led this group of teachers, many of whom are retired from public school with years of experience behind them. Test scores speak for themselves! Safety, probably one of the best on the east end with its name badges, electronic gates and security guards on duty on a regular basis.
—Submitted by a parent

Posted September 22, 2008

I am an alumni and send my children to Mercy. The Junior High program is excellent. The children are given every opportunity for advancement. My child has flourished. The High School has gone through many changes for the good. The principal & staff are first rate. Father Mike ties it all together. A+
—Submitted by a parent

Posted October 2, 2006

In the last few years with the addition of diocesan support, this school has done an excellent job in adding academic courses and extracurricular activities (incl. sports, music and drama) while still retaining the special spiritual, caring community established by the Sisters of Mercy. This nurturing environment is what makes this school so special. Children are not just a number here. They are seen as a vital part of this scholastic community and are encouraged to live and learn to their fullest potential.
—Submitted by a parent

Posted May 12, 2006

the quality is overall excellent.
—Submitted by a student

Posted May 2, 2006

caring environment, fine arts programs are growing- good drama dept parent involvement welcome
—Submitted by a parent

Posted October 18, 2005

Very small high school that is improving every year. Great principal.
—Submitted by a parent

Posted September 9, 2003

Mercy has been everything we had expected from a high school. The teachers are friendly and students seem to be in a family like atmosphere.
—Submitted by a parent

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About these ratings

The Community Rating is the school’s average rating from its community members (e.g., parents, students, and school staff). The highest possible rating is five stars; the lowest is one star.

We currently do not have any test score information for this school. Unlike public schools, private schools are not always required to report data about their schools or not required to take the same tests as public schools. Many private schools take different standardized tests; however, that information is often made available only to families of enrolled students. We strive to acquire additional private school data whenever available.

Student ethnicity

Ethnicity This school State average
White 91% 52%
Hispanic 4% 21%
Asian 2% N/A
Black 2% 21%
Two or more races 1% N/A
American Indian/Alaska Native 0% 1%
Asian or Asian/Pacific Islander N/A 6%
Hawaiian Native/Pacific Islander 0% N/A
Source: NCES, 2009-2010

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School facilities
  • Computer lab
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School basics

School Leader's name
  • Carl Semmler
  • Coed
  • Roman catholic
  • NCEA


Specific academic themes or areas of focus

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  • Religious


School facilities
  • Computer lab
  • Library
Partnerships with local resources and organizations
  • Diocese of Rockville Centre
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1225 Ostrander Avenue
Riverhead, NY 11901
Phone: (631) 727-5900


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