If a question likes this comes up during your interview, there is no need to fret as your interviewer is simply looking to hear your passion for working with a specific age or grade level. There is no right or wrong answer. If the position you are interviewing for will be focusing on a specific age or grade range, that will be spelled out in the details of the job posting and if that is the case, be sure to talk about your preference for that age. If this is a position that spans over an entire district, then feel free to speak openly and honestly about where you do your best work and describe why.