If you have a small team then everyone just does a bit of everything, BUT if you have more people these are the sort of jobs they can do.
The editor is the boss of the paper - they decide what sort of stories it should cover and let the staff know who is doing what.
A sub lets the writers know what stories are needed. They also check the stories and make any changes they think will make the story appeal to more people.
You could get someone good at art to do a cartoon for each issue of the paper, they could even do a comic strip.
A big sports fan who would go along to school matches and write you a report. They need to know the rules and scoring systems. Someone into lots of different sports would be ideal.
Someone who likes to research things in a bit more depth, maybe doing longer interviews with people rather than just getting a couple of quotes.
Photos are great for attracting readers to your stories. The quality can be a bit dodgy if you are photocopying your paper, so it's good to have someone who knows what they are doing with a digital camera. You probably also need to lighten the pictures some picture edit software before you paste them into your DTP package.
If you are getting your mag or paper professionally printed you can do a lot more with pictures, a picture editor will decide which shots are the best to use.
They write news stories. That could mean going to school events and coming back with a story, or maybe going to get information from several people and piecing it together to make a story that explains things clearly to readers.
You might need someone who is really good at digging up information. They would have to know how to use libraries and the internet.
Someone needs to decide how the paper should look. They can use artwork and design skills to get the pages looking really interesting. They will probably be pretty good with graphics packages on the computer.