The short answer
A manager hiring for a first job usually isn't expecting experience. Mostly they want to know three things: that you will show up when you say you will, that you can be friendly with customers and coworkers, and that you will learn. Every question below is a way of finding that out. Answer with something true you have actually done, in a sentence or two, and stop.
What a first job interview is like
It varies a lot. At a small local business it may be a short chat with the owner, sometimes on the spot when you drop off your resume. A large chain may add a phone call, a second interview or a group interview. The questions below come up often, but you won't get all of them.
Common questions, and honest answers
1. "Tell me about yourself."
Why they ask: It's an easy start, and they want to hear how you talk.
Keep it to about 20 seconds: where you are in school, one or two things you've done, and why this job. It's close to the intro you'd use when you walk in to ask for a job.
2. "Why do you want to work here?"
Why they ask: They want to know you chose them, not just any job.
One real reason is enough. Being close by counts: it makes it easier to get to every shift.
3. "When are you available?"
Why they ask: Someone has to cover every shift, so availability can be a major factor in who gets hired.
Be exact, and only promise hours you can really work. Saying yes to everything, then cancelling shifts, can cost you a first job quickly.
4. "Have you worked before?"
Why they ask: They're checking what you've done, not looking for a reason to say no.
Say it plainly, then give one thing that shows you're reliable. Never invent a job. Some managers check references, and a made-up job can end the conversation.
5. "What are your strengths?"
Why they ask: They want something you can back up.
Pick one strength and give the proof. "Hard-working" or "a people person" on its own doesn't tell them anything. The example does.
6. "What is something you're working on?"
Why they ask: This is the weakness question. They want to see that you're honest about yourself.
Choose something that is really true for you, and say what you're doing about it. Don't make one up because it sounds good in an interview, and skip "I'm a perfectionist".
7. "Tell me about a time you worked on a team."
Why they ask: Almost every first job is teamwork: covering for each other, sharing the work on a busy shift.
School projects, sports, clubs and family jobs all count. Say what happened, what you did, and how it turned out.
8. "What would you do if a customer was upset?"
Why they ask: Every customer-facing job has upset customers. They want to know you'll stay calm.
Knowing when to get the manager is part of the right answer, not a weakness.
9. "How will you balance work and school?"
Why they ask: They're asking whether you'll stay, and whether school will come first when it should.
Telling them ahead of time is what managers want to hear.
10. "Do you have any questions for us?"
Why they ask: Asking something shows you're interested.
Have one or two ready. It's reasonable to ask about pay and scheduling too, when the interviewer describes the job or near the end.
If you don't know what to say
It's fine to take a breath and say "Let me think for a second." If a question asks about something you haven't done, say so and answer with what you would do: "I haven't been in that situation, but I would..." An honest answer you have to think about is better than a smooth one that isn't true.
What to bring
A printed resume, even if you applied online, and your exact availability written down. If they ask for references, you can give them then or send them afterwards: one or two people who know you, like a teacher, coach or volunteer leader, who have agreed to be contacted.
After the interview
Thank them before you leave. If the day they said they'd decide passes, follow up once.
Practise out loud first
Saying an answer out loud is different from thinking it. Practise each one until it sounds like you talking, not something you memorised. Relaunch, which publishes this guide, can ask you questions like these about your own resume and follow up the way a manager might.