I'm looking for insight as to how other schools operate and how classes are structured.
Loosely. We generally will have warm-ups, stretching, then work on poomsae, bag work, paddle work, and specific techniques (punching, kicking, grappling, breakfalls...). We generally do sparring one day a week. But all of that is subject to change on the whim of the instructor. Maybe a student will ask a question, so we dive into answering.
On ranking, do you have an idea of the requirements or is it simply up to your teacher to decide when you are ready?
Both. Our minimum rank requirements are set forth in the school textbook. Students can be asked to demonstrate additional things, if we have time, but it is always material that they have been taught.
Students can ask if they're ready to promote, in which case they are either told "yes" or are shown what they need to work on. Nobody tests until the instructors are confident in the students ability.
My view is that there is no test. They're simply being given the chance to show off for friends and family. Nobody fails. If a student is unable to perform at the exected level, they try again. It's pretty much always a case of test anxiety. Occasionally, younger students may have difficulty doing the mandatory break (minimum 1 board with a technique based on their rank). I cannot recall the last time a student couldn't pass the poomsae or sparring sections.
Is there a difference between material taught to kids and adults?
Sort of, but not really. An example.
In Koryo, there are several arc hand strikes. There are several applications for these, with wildly differing goals. One portion of the form shows the strike attacking the knee, after catching a kick. Another striking higher, in the head/neck area. This latter application can be done with at least three goals.
1 - Targeting the point of the jaw. I do teach students to avoid hitting the mouth itself. Bites are nasty. They are pretty much the only wound that will always get antibiotics.
2 - Targeting the underside of the jaw, at an upwards angle, to unbalance your opponent.
3 - Targeting, the throst. Specifically, the hyoid bone. Hyoid bone fractures cause rapid swelling, will block the airway in a very short time, and have a very high mortality rate.
So when students are at a rank high enough to learn Koryo, we have a conversation. The short version is "ask yourself what you're willing to do and be brutally honest. If you don't think you could ever use the final version, don't bother training it. Train what you will use."
We don't have baby black belts, so this conversation is going to be with an adult, or in rare cases a 16-17 yo.
Are ranking standards consistent or do people's skills vary even in the same rank?
Our ranking standards are very consistent. There will always be differences in individual skills. One may have really pretty technique doing poomsae but not be much good at sparring. Or the other way around.