Groton has 8th graders rising into 9th grade so there are not many available spots resulting in a very low rate of admission.
Groton
For fall 2015 : 1,560 applications received. 158 Accepted (10%). 98 enrolled.
Middlesex :
For fall 2016 : 1,173 applications received. 216 accepted (18%). 113 enrolled.
For Fall 2019 : over 1200 applications. 19% accepted.
@bostonbloke
as @Publisher has noted Groton is not a purely 9-12 school and thus it is important to view data in context.
Groton’s position as a school with lower grades allows it lower admission rates, and regardless I think ultimately both of these schools are highly regarded and your choice should not consider too much the ranking between two very competitive schools. In other matters Groton and MX are rather diverse, so see where you fit in and chose the school with the community and style that makes you happy.
IMO The numbers game for admission rates, at this point, should really not even be something you are considering as a comparison point. These numbers change, they are not definitive, should not be taken out of context, and ultimately are only one factor of many in the ranking and reputations of both schools.
Groton had about 1200 applications this year for 90 spots in 8,9,10,11. I don’t think it had 1560 applicants in 2015 - if that were the case, their application numbers would be in free fall, falling 20 percent in 3 years. I think Groton normally has around 1200-1250 applicants. It has a 9th grade class of around 65-70 kids, and with 25 8th graders, this means they only admit around 40-45 9th graders, and 20-25 10th-11th graders.
Their 8th grade doesn’t really distort their low acceptance rate - they have a lot of applicants for that grade as well. It’s simply admits/applicants, regardless of the grade year. It has a relatively high number of international applicants because of its renown, so domestic admit rates are higher than 12 percent. It also has a relatively high percent of legacies. It has around 320 boarders.
Middlesex has around 68% boarders, a high yield for day student applicants, and relatively low yield rate for boarders compared to its peers. It has around around 275 boarders.
As the only top boarding school offering an 8th grade, it does distort their low admit rate for both 8th & 9th grades.
Not sure if still true, but when I last visited Groton, all 8th & 9th graders were housed together in an open type dorm. Is this still the case ?
@Publisher The existence of Groton 8th grade would only distort the acceptance rate for the school as a whole (lower than 12 percent acceptance rate in 9-10-11) if the 8th grade acceptance rate was significantly above 12 percent. Is that the case? I’ve never heard that.
We are heading to revisit at Groton with son this week. Then SPS and Deerfield. I LOVE Groton for the small feel and amazing admin office and staff. The comment about kids being less warm concerns me because our interview gave me that feel, compared to other schools. I am hoping revisit adjusts our view as I really feel that Groton cares deeply and nurtures their kids.
@boymom928 We did not/do not think the Groton kids are less warm. Our Groton tour guide was the best of all the schools we visited, a real gem. While I was wandering around the hallways looking at stuff while my daughter had her interview I was approached, at different times, by several students asking if they could help me find something or did I need anything. We have spent time at games and found the student body very lively in their vociferous cheering for their teams. No lack of warmth at any time. Not sure where you are originally from but I know most new englanders seem less warm to people from other parts of the country.
Good to hear! We are very open minded as Groton has been our top choice for 2 years. The coaches and staff are certainly the most welcoming and interactive. They have really made us feel wanted. But nice, down to earth and friendly kids are going to be key to a good 4 years. Maybe we will see you at revisit!
Groton has zero issue with warmth. That’s a single person’s opinion. In fact, the small size keeps the schol very friendly. And the head of school, already mentioned that s very embracing.
A parent here mentioned Groton kids sitting on steps and refusing to move ever so slightly to make way for a group of visitors touring the school.
Again: One family’s experience only. Might not be typical.
@CaliMex , that seems like a gossipy, petty comment. Some vague reference about kids on steps from “a parent here”? Really? What post was it? Seems like poor quality for you to be offering up weak 3rd party points from people you don’t even know.
@CMKDad It was just one person’s experience. Take it however you’d like. Sounds like your experience was completely different.
Post #13 here: http://talk.qa.collegeconfidential.com/discussion/comment/20981851#Comment_20981851
Can’t find the thread where she mentioned it was Groton.
MODERATOR’S NOTE:
In the spirit of this,I have deleted the back-and-forth bickering.
Thank you, @skieurope
@CaliMex we revisited Groton last Thursday and Friday and we found the kids at Groton extremely happy and very warm. Our DS spent some time playing ping pong with a few of them and had a blast. We found that Groton is almost like a large family and that theme was repeated often by current parents and teachers at the event.
That’s great, @ReluctantDad
Sounds like your son found his peeps and you found the right school for your family
We did, our DS will be attending Groton.
@ReluctantDad Welcome to the fam! 
@ReluctantDad I would highly recommend any class with David Black, the greatest teacher I ever had! Welcome to Groton!