The reason for asking about the last school attended can vary. It could be for employment purposes, where employers want to know the educational background of candidates to assess their qualifications for a specific job. It can also be for academic purposes, such as when applying for higher education programs, where information about previous educational experiences is required.
In some cases, the term "last school attended" may also refer to the most recent educational institution an individual has completed. For instance, if someone attended both college and graduate school, their last school attended would be the graduate school they completed.