From basic kindergarten to high school to college or university, every class that you are in will have a set curriculum the teacher will follow. Every teacher works in tandem with the school system to come up with a curriculum that they believe will impart everything the students in the class need to learn that will help them once they move on to a higher class or in their future career.
All formal education has a certain set of content that needs to be taught in specific classes. For instance, Mary who is in high school, wants to one day become a dental care professional, will be taking health and science classes with set curriculum that will teach them certain things needed to become an dental hygienist or whatever she chooses . That's what any class is like. A junior kindergarten class curriculum will cover certain topics such as sharing, reading, art and math.
The curriculum for every class and every level of schooling will be different and will be based on the level of education the students in the class have previously had. Someone who wants to be a financial planner and is in business school won't be in a management class if they haven't taken a basic business class before registering for the more specific course.
Curriculum's must include specific topics that will be covered throughout the course of the year and are tailored to the current grade or class level that is being taught. Kids start off in a basic kindergarten class and keep graduating to a higher class and the curriculum that's set will be one of many factors that will elevate children from the lower grade to the higher grade and that will continue to be done throughout educational lifespans of children all the way into adulthood when they're using their skills.
At the beginning of the school year a syllabus will be handed out to students that details the curriculum that will be taught for the year. This is a valuable tool, as you will know what is being taught, when it will be taught and for how long a certain subject will be taught.