Hand in vs. Hand out

If you hand something in, you are giving something to a person of authority. If you hand something out, you are giving something to a group of people. 
Hand in = a group of people giving/ submitting something to one person  
Hand out = One person giving something to a group of people.

1. It’s a “madhouse” trying to hand out sweets/ candy to a bunch of kids at any party. They will crowd around and attack you… so it’s best to throw the sweets into the air and watch!

2. When you were at school, were you one of the responsible kids who used to help the teacher hand out the worksheets? In any class, one person can hand out the worksheets or the group itself can just pass them around, which means that each person takes one and passes the rest on. If you ask someone to hand something out for you, you can also say, “Could you please pass these out for me?”

3.  Have you ever handed out pamphlets or flyers in a public place to promote anything?

4. A handout is something that you give for free/ donate to someone. If someone is too proud to accept financial or material help, they will say, “Thanks but I don’t need any handouts”.

5. Everyone needs to hand in (submit) their income tax declaration before a certain date.

6. When students at high school or university don’t hand in their assignments or projects on time, usually the teacher/ professor will take off (deduct) 5% to 10% for each day past the deadline.

7. A couple of weeks ago we handed in our papers for our permanent residence visas for Brazil. There was a lot of bureaucracy but in the end we were able to submit them on time.