Informational interviews provide a great, low-stakes way for students to learn from other people, and explore things they are interested in before they go to college or enter the workforce.
This document outlines four types of informational interviews and some questions students could ask. Students are provided example three types of copy they could use to send a request to their prospective interviewees. A post-interview prompt is provided for students to submit for your review.
I would suggest covering the content in class and then assigning it as homework or an extra credit assignment.