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GreatSchools Ratings FAQ

Read these Frequently Asked Questions to learn more about how GreatSchools Ratings are calculated and what they can tell you about a school.

GreatSchools Blog

By GreatSchools Staff

GreatSchools Ratings Overview

What do GreatSchools Ratings tell me?
Which tests are GreatSchools Ratings based on?
Why don't private schools have GreatSchools Ratings?
Why do some public schools not have GreatSchools Ratings?
Can I compare GreatSchools Ratings across different states?

GreatSchools Ratings Calculation

What data is used in calculating GreatSchools Ratings?
How are the "By Grade" ratings calculated?
How are the "By Category" ratings calculated?
How are the Overall Ratings calculated?
Why are some student groups not shown?
How can a school's Overall Rating be high if the ratings for certain student groups are low, or vice versa?
How are the District and City Ratings calculated?
What is "weighting" and why is it used in District and City Ratings calculations?
Why do some districts and cities not have GreatSchools Ratings?

GreatSchools Ratings vs. Other Ratings

How do GreatSchools Ratings compare to the ratings given by the state Department of Education?


GreatSchools Ratings Overview

What do GreatSchools Ratings tell me?

Our ratings provide an overview of a school's test performance by comparing the school's state standardized test results to those of other schools in the state. Ratings are given for each grade and student category (gender, ethnicity or other student group) for which test results are available. Keep in mind that when comparing schools using GreatSchools Ratings, it's important to factor in other information, including the quality of each school's teachers, the school culture, special programs, etc.

Which tests are GreatSchools Ratings based on?

GreatSchools Ratings are based on each state's main standardized tests. To get the details on specific tests used in your state, go to any school's ratings page and click on the link below the ratings that says "See which tests were used."

Why don't private schools have GreatSchools Ratings?

Private schools are not required to publicly report test results, so they do not have GreatSchools Ratings.

Why do some public schools not have GreatSchools Ratings?

If a public school does not have GreatSchools Ratings, there were no test scores reported for that school, results were incomplete or there were not enough results available across all schools in the state to make a valid comparison.

Can I compare GreatSchools Ratings across different states?

No, GreatSchools Ratings cannot be compared across states, because they are based on test results and different states use different tests.


GreatSchools Ratings Calculation

What data is used in calculating GreatSchools Ratings?

GreatSchools Ratings are based on the most recent available standardized test results for schools in each state. The results we use are typically the percentage of students scoring at or above the proficient level on the test in each grade and subject (e.g., grade 4/math) and each grade, subject and student category (e.g., grade 4/math/Hispanic students). The proficiency levels and student categories are defined by the state Department of Education.

How are the "By Grade" ratings calculated?

We start by calculating ratings for each grade/subject combination; then we average those ratings into the By Grade ratings you see on the page.

The test results for all schools for a given grade/subject are sorted from low to high and divided into deciles, or 10% portions. The bottom 10% of schools get a rating of 1, the next 10% get a 2, on up to 10, which indicates the school's result is in the top 10%. If there are several identical values that overlap from one rating decile to another, they are given the higher rating.

Once ratings are established for all grade/subject combinations, each school's ratings are averaged to create the By Grade ratings that you see on the page. For example, the rating shown for grade 4 is an average of that school's ratings for each subject tested in grade 4. If the grade 4 rating is a 10, it means that, on average, fourth-grade students at the school performed better than 90% of the fourth-grade students whose test results were reported at schools statewide.

To ensure that the ratings are not based on a set of data that is too small to be statistically reliable, a rating is not calculated if fewer than 50 schools reported test results for a particular grade/subject combination.

How are the "By Category" ratings calculated?

The By Category calculation is similar to the By Grade calculation. We start by calculating ratings for each grade/subject/category combination; then we average those ratings into the By Category ratings you see on the page.

The ratings for each student category provide an alternate view of a school's performance, comparing the performance of a given group of students at the school with the overall student population of the state. The categories are defined by the state. For example, the California Dept. of Education releases separate test results (called disaggregated results) for 26 student categories, including gender, ethnicity and special student groups (e.g., students with disabilities).

To create the ratings for each category, we compare the performance of that category in each grade/subject to the decile rankings we have established for that grade/subject. The performance value used is the percentage of students in the category scoring at or above the proficient level, as defined by the state.

You can use the By Category ratings to compare student groups at the school. For example, if one category receives a rating of 3 and another category receives a rating of 7, this suggests that an achievement gap exists between these categories of students at this school.

How are the Overall Ratings calculated?

The Overall Rating for each school is calculated by averaging that school's ratings for all grade/subject combinations. For example, if a state test is given in reading and math in grades 3 through 10, the Overall Rating for a school serving grades K-5 would be the average of the ratings for grade 3/math, grade 3/reading, grade 4/math, grade 4/reading, grade 5/math and grade 5/reading.

Note that the Overall Rating is not an average of the By Grade ratings you see displayed on the page, but rather, an average of the underlying grade/subject ratings, which are used to create both the By Grade ratings and the Overall Rating. We use these underlying ratings, instead of averaging the By Grade ratings, to reduce rounding errors.

Why are some student groups not shown?

The different student groups shown in the By Category section are defined by the state Department of Education. To protect students' privacy, if there are fewer than 10 students in a group, that group's test score is not publicly reported. If no test results are available for a particular student group, no rating can be created for that group.

Find GreatSchools Ratings for a particular school: Search now

How can a school's Overall Rating be high if the ratings for certain student groups are low, or vice versa?

If a school's Overall Rating is high, that means its test scores are better than the test scores of most other schools in the state. If a particular student group's rating is low, that means the test scores for that particular group are lower than the scores of most other students in the state. This may mean the school is helping most students achieve at a high level, but is not serving particular groups of students as well.

Conversely, if a school's Overall Rating is low, that means its test scores are lower than the test scores of most other schools in the state. If a particular student group's rating is high, that means the test scores for that particular group are better than the scores for most other students in the state. This may mean the school is helping certain groups of students achieve at a high level, but is not serving the majority of students as well.

How are the District and City Ratings calculated?

District Ratings are calculated by taking the Overall Rating for each school in the district and weighting it by the number of students enrolled at the school. We then take the average of the weighted ratings. Similarly, City Ratings are calculated by averaging the weighted Overall Rating for each school in the city.

GreatSchools Ratings are based on each state's main standardized tests. To get the details on specific tests used in your state, go to any school's ratings page and click on the link below the ratings that says "See which tests were used."

What is "weighting" and why is it used in District and City Ratings calculations?

Weighting each school's Overall Ratings means that schools with more students count more than schools with fewer students. Weighting makes the District and City Ratings more representative of the performance of the entire student population.

Why do some districts and cities not have GreatSchools Ratings?

District and City ratings are not created if there are too few schools with ratings in the district or city. For districts and cities with fewer than 10 schools, at least 50% of the schools must have ratings in order for the district or city rating to be calculated. For districts and cities with 10 or more schools, at least 30% of the schools must have ratings.


GreatSchools Ratings vs. Other Ratings

How do GreatSchools Ratings compare to the ratings given by the state Department of Education?

Some states have their own ratings systems, and their method of calculating ratings may differ significantly from the way GreatSchools Ratings are calculated. GreatSchools Ratings are based solely on test performance for one year. Check with your state Department of Education to find out if your state has a rating system and how its ratings are calculated.

Comments from readers

"apparently, this site is not interested in actually answering questions. I came to this page looking for an explanation of the shields and handprint icons and note that the previous commenter asked the same thing nearly six months ago. this system needs a simple explanation and they can't find a way to do it. this makes me have less interest in using this site at all. "
"What do the shields and the handprint icons in the ratings column mean? "
"Parent comments over 3 years old should be omitted from the community ratings and eliminated from this website. Definitely eliminate old comments more than 4-5 years old! You still have comments from 2007 listed as a reflection of multiple schools. My child's school has had 3 different principals since then and is a totally different environment. Need to set some parameters around making sure comments are timely. "
"What is this "great school" rating business? I thought rankings were based on TAKS testing and the top ranking to strive for is "exemplary school". I know for a fact that my children's schools have the "exemplary" ranking and none of this ridiculous "great school" stuff. Seems they create special ratings for schools who don't meet the standard TAKS test levels. "
"What the differences between Greatschool ratings and Community ratings?There are some symbols on Greatschool symbols,which have different colors,and has number in red,what do they mean?Thanks. "
"Wait a minute. State tests are not standardized tests. They have not met the criteria of reliability, validity and norms. We have lost our minds with this testing mentality. It dictates curriculum. And yet, can we be assured that the test designers have determined what needs to be measured? "
" what is Watterson Elementry doing to raise rating "
"I truly appreciate this site. The rating is simply a number based on how well the students in a particular school scored on state tests. Why is there so many negative comments? Obviously better schools have better teaching methods which produce better test scores! I have been contemplating moving to another area of the state and I find this site very useful. Thanks Great Schools! "
"What do you mean "Economically disadvantaged"? What is the standard to rate this? "
"its kinda funny how the rating is based on the test since my childs test results are ommited because she is so far behind and get low grades and the teachers and other adults will not work with my child at her needs of learning. that is why my childs grade is not included. the ratings should include parents input like how the child is getting the help they need to suceed and how the child is being dealt with in situations like being bullied or being treated by some teachers. we need more inputs from parents on the rating of the schools so maybe something will be changed so the teachers dont look bad by not stepping up and dealing with issues that arrise in the school."
"I can get the same information that is used for ratings directly from each state's Department of Education website. However, the state websites do not provide a link to buying a home. At least not yet. . ."
"again you are taking Southmoor Elementary, Denver, Co. scores on the whole school. this school runs a highly gifted class for each grade thus when they figured the scores all classes are used andof course that raises the score. Try using just the regular classrooms and see where the score is, i am sure it won't be as high."
"Do you seriously think most kids from the low income,broken homes and drugs infested streets have better test scores than kids from well educated, professional,and family oriented type of neighborhoods ? Go to the schools with the low rating and the schools with high rating, and find out for yourself. "
"Everyone is freaking out about how they do their rating system but none of them are taking into consideration that they also list test score averages AND parents comments about the schools. Everyone has to look at the whole picture, not just focus on one thing. The rating that is given is only a very small part of what you should be considering when choosing your child's education."
"Oregon OAKS testing is not standardized testing. It's a benchmark test of what a panel thinks is appropriate to know at a given grade. The NAEP test is a standardized test used nationally starting at grade four."
"I also believe that basing a school's rating just off the standardized testing scores is not the best way to rate. What I don't agree with is the comments that say GreatSchools are biased towards rich schools. "
"In reviewing the 'GreatSchools' site, it is my belief that this is a piece of propaganda that works well with the concept of basing a school on a test. This is disappointing. I will be forwarding this information to my friends. I hope that you will find the correct information on CT schools and other state schools in the future. I will be unsubscribing from your e-mails. I hope that in the future you will provide accurate information."
"It seems that a lot of folks are unhappy with the way the ratings are calculated. Also, I noticed that some of you think that schools that receive a rating of 8 or higher are 'rich' schools. If you connect to the website (this is for Missouri) or any other online demographics map that you are able to break down by income you will see that the schools that receive high ratings are not necessarily high income areas. I'm from a very poor community and the school that my daughter will be attending next year has a rating of 8. I don't believe that the testing used tells all about a school but I do think if the majority of the students are able to achieve high grades then they must be learning something. "
"While I do agree with other postings that standardized testing alone should not be a sole determination of how your website calculates a school scores. I think parent involvement,staff communication with parents, teachers professionalism, principals leadership...all of those items could be potentially included... However I will say when I moved to a new area in my city I checked the schools in my daughters district for ONE particular school their test scores and that school scored about a 93% in all AIMS test and you rated it a 10...I decided to move her to this school based a visit to the school and yours and other school based scores....WOW am I glad I did. Her old school was a complete mess and now she is in an excelling school and not in an underperforming underfunded school. With that being said THANK you !!! So I am happy with your site and keep up the scores and information...!!!"
"If you would realy do the homework MPS are not rated that well.Most parents dont have a chose where they can put there kids in schools.MPS just foces on one thing and its how your child looks and if they are up to there standerds! and if you dont have some what of money they you have no right to give out your opinion. say if they are wanting to put school uniform's and they call parents and aske if they approv and the parents say no they would say we will call you back when you have more time to think about it and if they still say no they will say somthing like will most parents want it. even if its not true! do you know why they closed down Powlle Jr high? the real truth is that they were one of the worst schools they were not meeting states req and so befor the state took over they closed the school down and made it in to a education center so that they will look like they are doing great and that the public wont find out. I used to work for MPS and i still have close fri! ends and fam working there. everything is online you just have to have the time to look at what the reals scores are and what the parents are saying. "
"my daughter is attending school 29 since pre k and I can say this is an excellent school. Teachers are very professionals and kind with children and they learn a lot.My daughter really love this school and my wife and me are very happy about our little girl attending her first school years here. thanks school's 29 team."
"The GreatSchools Rating is completely meaningless. It should be removed from the site altogether. Newsweek named Columbia Heights Education Campus (Bell Multicultural HS) #77 overall in the entire US and #12 in the DC metropolitan area. GreatSchools Rating: 4 out of 10. This site is only good for finding the private school Obama sent his kids to."
"As parents and grandparents we have a voice. I never knew what this test was for, but after looking at scores I realized those voicing a concern as to home values increasing the scores is correct. Perhaps it's time for parents to step in and say no more nationwide..."
"Like many standardized tests, crts, do not take into account the starting point of a child's knowledge. Individual growth is far more important than schools state ranking. This becomes even more important when dealing with Title 1 schools. MAP testing is a truer measure of a schools accademic worth because it shows how much an individual student has grown in math, language, etc. in a year. I believe many of the schools which received lower rankings had children with far lower academic starting points than those receiving higher rankings. Give props the fantastic teachers and schools who don't care how much money you have or the part of town you live in, but instead focus on teaching to an individuals level and in turn pushing for personal growth and responsibility"
"I absolutely think the site favour areas where rich people lives rather than the overall. I am glad I do not have to base this site to my decision. "
"If you are 'not for profit,' why are there ads (and annoying pop-ups)on your website?"
"I am probably preaching to the choir. But seriously, how do you come up with your overall ratings. If you say you are going strictly by the standarized test scores then the a majority of the schools in my district should have an 8 or higher. All of our schools have exceed state and a national expectations. And yet only the 'rich' schools got an 8 or higher. The schools that have high diversity scored 6 or lower. Seems a little suspect to me. Schools that got Blue Ribbon Honors from Washington year and year out received low overall scores. This site actually FRIGHTENS me. In our part of the world we are fighting 'white flight' on an hourly basis and you just added fuel to the fire. I just had a family tell me they are moving out my school district because you gave it a 6 and Blue Valley a 9. Good luck with finding anyone who is not white in Blue Valley!!!! This is just another website fueling the racist card once again. And this SADDENS ME!!!!!!!! And really not! for profit and you have all this advertising. How much are you getting paid in Sr management? Seriously, if NETFLIX pops up on my screen one more time and I have to close out their tab I think I will scream. It saddens me that a family I know is going to make a home purchase based on false information. It just amazes me as the property values increase the school overall rating increases. WOW! "
"GreatSchools Rating is 1 through 10 and is 1 being the best ?"
"I want to know where the WASL test is gettting the information about the families income? Im reasearching schools in my area and one of the issues I had was the fact that students were being rated based on they're parents income! Really! But really, where do they get this informtion? Is it from the students or from the parents. We are not economically challenged or Low income as the two categories were put, however the school of interest to me is said to give a rating of a 2 to low income children vs. an 8 to 'not economically challenged' students. I beleive we fall into the 'not economically challenged' category but should I be worried about that!? Where does this perticular information come from? "
"When looking at a school rating, please be aware that the rating generated from standardized tests scores are sometimes initially incorrect. Make sure you follow up and note any changes..."
"What does an ethnicity rating mean under category? The school that I was looking at had one ethnicity and then a grade of 9 assigned to it. What does that mean?"
"Good teaching is ongoing and should be occuring everyday of the school year. Children are not learning to master a test. They should be applying what they have learned to master the test, because they have been provided with excellent teaching- We need to focus on the quality of instruction and then the tests won't consume the entire year with worry, prep and overall boredom-how about some real interactive learning that can be applied in all areas? The kids deserve the best!!!"
"Your explanations were very helpful. We are in the process of selling our house (hopefully) and, judging by my daughter's school's (low) ratings, will be looking elsewhere for another house. Thank you, M. Parker"
"You should find out if other, nearby schools are in better shape. Usually during the month of May-June, schools outside of your neighborhood will accept applications for 'open enrollment' or 'out of the area enrollment', based on first-come-first-served, sometimes by lottery of all applications received during a certain period of time. You may also apply for 'opportunity transfer' because of the school's probation. In some districts you can apply to a different school if your local school is predominantly a race OTHER than yours, and would put your child in a significant minority. You can apply to the school in the neighborhood of your / your husband's job under 'work permit', even if it is a different school district. Finally, you can apply to the neighborhood school where your child will receive after-school childcare, even if grandparent or relative, under 'child care permit'. "
"I am going to use your checklist and get back with you on my concerns."
"Hi, A good first draft of the article, but your middle school teacher would ask you where is your critical thinking and where is your voice. The Article does not touch an several VERY important aspects of the testing. Here is a short summary: 1) The STAR test is presented as MANDATORY by most schools. it is NOT. Parents can always opt out their kids from the test. And parents should educate themselves as to why they want their kids in the test vs not in the test. 2) The star test measures broadly and test scores can be seriously impacted by teaching memorization techniques. Several high-scoring schools are spending a LOT of time teaching to the tests in order to get better scores. There are several other tests such as the MARS test developed by the Silicon Valley Math Initiative that measures comprehension. So these tests goes far deeper than the STAR can go and they are scored based on the result and on how the student obtained that result. Unlike the STAR the MARS is scored by humans, so the students task in the test is to convince the graders that they actually understand the questions. 3) Many high scoring STAR test schools that also participate in the MARS often score poorly in the MARS - back to my point about memorization. 4) The STAR test is not used for Middle School, High-School nor College placement nor applications. Does that mean that a teacher at a school that wants to get a picture of a student will not look at a the students test results - sure, but that only shows one part of the picture. 5) A teacher once walked us through the test. Amazing number of objections to the test and what it does to teaching. The best example is spelling. The test provides the students with a list of words out of which only one is spelled right. The student has to identify which one. This teaches the student how to identify misspelled words, but does ABSOLUTELY NOT teach the students how to spell on their own, and even less how to write. 6) The only statistical proven correlation between STAR testing scores has been to house pricing. So are we asking our kids to go through all this trouble for housing pricing ? 7) Do we need a system to provide feedback to the teachers and administration on how classrooms are doing. Surely - but the STAR is not that answer. Too broad and does not measure comprehension so therefore not very suitable for this purpose. 8) Many kids feels so pressured to take the test and are so stressed out over the fact they have to perform well that they suffer from anxiety. Now ask your self if this is right for elementary school kids. 9) The STAR test takes 2 weeks to administer with approximately 3 hours of testing per day. 2 WEEKS of instruction time WASTED !!!!! Imagine what your child could have learned by spending this time on say a independent research project. 10) The STAR testing is EXPENSIVE. My school district spends approx $1M on the testing. I ask how come we can afford to keep doing this with the significant budget cuts that has been implemented across many states. "
"My granddaughter (going into Kindergarten in the fall) has been assigned to a school that is on academic probation with a rating of 3. Besides private school, what are our options? Can we ask, based on the low rating, to go to another school?"
"Draper, UT is now in the newly formed Canyons School District."
"I don't understand this rating system. If this is based off of state test scores then how can a school with 80% of its students passing get a 1 rating while schools in the same area get a 6 with around 70% of students passing and a 3 with a little over 50% of its students passing the standardized test?"
"I presently teach at Ingram Elementary School and would like like to know who did the ratings for our school. A 4 is so totally off the stae ratings that I have to laugh. So could you please tell me who does the ratings and what you used to compile your information. It is totally wrong. "
"Please, enough already. This website is a TOOL! If you are not willing to do the work yourself, don't complain. There is not going to be a free site available that is going to be all things to all people. Accept the fact that this is a tool, only a tool and nothing but a tool. Do your research, write letters, make phone calls; then make an INFORMED decision based on all the available data. Don't depend on anybody else to make this decision for you. End of story!"
"There's so much more than test scores to rate a school or school system. What about the way children are treated and handled? Are they encouraged to explore their individuality or punished for it? Schools in these times have gotten far from their TEACH. I would not rate DePere schools highly. Alas, focus is away from teaching a student. If this keeps up, everyone will start resorting to home school...and why not?"
" The school ratings from test results are extremely low in comparison to school ratings from parent reviews. If GreatSchools' mission is to improve education, then it must raise awareness or acknowledge the issues of assessment. Every parent wants their child to attend a 10 out of 10 rating school. So imagine all parents being influenced by GreatSchools wanting to enroll their students in a 10 out of 10 rating school... Realistically, there would not be enough schools to support such high demands for enrollment. So, what does that mean for a parent whose child attends a 3 out of 10 rating school? It means a slap in the face! Hence, GreatSchools has many parent reviews and comments about the negative impact that such ratings may have on them (the parents) and the schools. If parent involvement is important to GreatSchools, then this organization should address the concerns parents have raised about the ratings and acknowledge the impact this may have on parents and schools."