Kidney stones are urinary disorders that occur when there is an excess crystal-forming substances such as salt / chemicals in the urine. These stones can restrict the flow of urine, and lead to serious complications including infection, kidney damage or even kidney failure. Kidney stones consist of various types of chemicals including calcium, phosphate and oxalate.
Kidney stones affect men more than women between the age of 20 and 40. Different types of kidney stones are composed of different chemicals including:
- Calcium oxalate stones or calcium phosphate stones (the most common type)
- Cystine stones
- Struvite stones
- Uric acid stones
Kidney stones occur when:
- the urine lacks, or has low levels of substances that usually inhibit minerals from sticking together, known as “crystallising".
- the urine contains more minerals (such as calcium, oxalate, phosphate, uric acid or cysteine) than it can dilute.
- there are other conditions such as cystic kidney diseases, urinary tract infections, and some metabolic disorders.
In addition, various risk factors may increase chances of developing kidney stones:
- Dietary factors include low intake of fluid and high intake of salts, oxalate-rich foods (e.g. peanuts, almonds, strawberries, tea and coffee), and purine-rich foods (e.g. organ meats, shellfish)
- Environmental factors such as living in a hot climate where you sweat excessively and have low fluid intake, this may leads to reduced urine volume and increased mineral level in urine.
- Genetic factors including a family history of kidney stones increase the chance of stone formation.
The symptoms of kidney stones include:
- Blood in urine
- Difficulty urinating if stone is too large
- Nausea and vomiting
- Pain when passing urine
- Severe pain on the back and flanks of the abdomen, radiating towards the front and groin area
Various treatment options are available. Doctor will assess the patient’s condition and suggest the most appropriate treatment according to the size and type of kidney stones.
If the kidney stones are small:
- No treatment is required. With plenty of water, the stones may eventually pass out in the urine
- Pain killers may be prescribed to alleviate pain during the passing of the stones
If your kidney stones are large, the following treatment options are available:
- Extracorporeal Shock Wave Lithotripsy (ESWL) - a non-invasive procedure where shock waves are sent into the body to break down the kidney stones into smaller pieces, which then pass out in the urine over the next few days.
- Medication - prescribed to help break down the stones. However, this option depends on the type of kidney stones patients have.
- Percutaneous Nephrolithotripsy (PCNL) - A surgery that involves making a small incision in patient’s back to allow a special instrument (nephroscope) to be inserted into the kidney to locate and remove the stones.
- Uretero-Renoscopy (URS) - A surgery where an endoscope is inserted through the urethra, into the bladder and to the kidney to where the stone is positioned. The stones are then broken down and removed.
Below is an extract from a web page. Evaluate whether the page has a high educational value and could be useful in an educational setting for teaching from primary school to grade school levels using the additive 5-point scoring system described below. Points are accumulated based on the satisfaction of each criterion:

- Add 1 point if the extract provides some basic information relevant to educational topics, even if it includes some irrelevant or non-academic content like advertisements and promotional material.
- Add another point if the extract addresses certain elements pertinent to education but does not align closely with educational standards. It might mix educational content with non-educational material, offering a superficial overview of potentially useful topics, or presenting information in a disorganized manner and incoherent writing style.
- Award a third point if the extract is appropriate for educational use and introduces key concepts relevant to school curricula. It is coherent though it may not be comprehensive or could include some extraneous information. It may resemble an introductory section of a textbook or a basic tutorial that is suitable for learning but has notable limitations like treating concepts that are too complex for grade school students. 
- Grant a fourth point if the extract highly relevant and beneficial for educational purposes for a level not higher than grade school, exhibiting a clear and consistent writing style. It could be similar to a chapter from a textbook or a tutorial, offering substantial educational content, including exercises and solutions, with minimal irrelevant information, and the concepts aren't too advanced for grade school students. The content is coherent, focused, and valuable for structured learning.
- Bestow a fifth point if the extract is outstanding in its educational value, perfectly suited for teaching either at primary school or grade school. It follows detailed reasoning, the writing style is easy to follow and offers profound and thorough insights into the subject matter, devoid of any non-educational or complex content.

The extract:
Kidney stones are urinary disorders that occur when there is an excess crystal-forming substances such as salt / chemicals in the urine. These stones can restrict the flow of urine, and lead to serious complications including infection, kidney damage or even kidney failure. Kidney stones consist of various types of chemicals including calcium, phosphate and oxalate.
Kidney stones affect men more than women between the age of 20 and 40. Different types of kidney stones are composed of different chemicals including:
- Calcium oxalate stones or calcium phosphate stones (the most common type)
- Cystine stones
- Struvite stones
- Uric acid stones
Kidney stones occur when:
- the urine lacks, or has low levels of substances that usually inhibit minerals from sticking together, known as “crystallising".
- the urine contains more minerals (such as calcium, oxalate, phosphate, uric acid or cysteine) than it can dilute.
- there are other conditions such as cystic kidney diseases, urinary tract infections, and some metabolic disorders.
In addition, various risk factors may increase chances of developing kidney stones:
- Dietary factors include low intake of fluid and high intake of salts, oxalate-rich foods (e.g. peanuts, almonds, strawberries, tea and coffee), and purine-rich foods (e.g. organ meats, shellfish)
- Environmental factors such as living in a hot climate where you sweat excessively and have low fluid intake, this may leads to reduced urine volume and increased mineral level.

After examining the extract: 
- Briefly justify your total score, up to 100 words.
- Conclude with the score using the format: “Educational score:  <total points>”

Remember to assess from the AI Assistant perspective, utilizing web search knowledge as necessary. To evaluate the response in alignment with this additive scoring model, we’ll systematically attribute points based on the outlined criteria.