* Country: Different countries have different regulations.
* State/Province: Within a country, individual states or provinces often set their own minimum requirements.
* School District: Even within a state or province, school districts may have slightly different policies.
* Grade Level: The required hours might differ between elementary, middle, and high school.
To find the specific number of hours required for a particular school, you'd need to check the regulations of that school's governing body (e.g., the state department of education, the school district, or the school itself).