So, this is my guide to prevent this from happening to new users.
Giving out info.
Don't give out any personal information here, like numbers, or mails. It's really unsafe, and it could lead to cyberbullying, and even random people turning up at your house. Remember: What's put up onto the internet, everyone can see it. Not just your 'best friend'
Hacking on Kidzworld is impossible. Yes, sometimes people give out their pass, but sometimes people's passes are easy to guess, so I would recommend, when coming onto KW, make your pass full of numbers with upper and lower cased letters. If you want someone to write a nice message on your profile, just tell them to comment it to you, and you can copy and paste it onto your profile.
If you see something inappropriate on KW, you are really supposed to report it to the mods, and try to help. If someone bullies you, there's a report button, and you can tell any mod. Also, tell an adult you trust.
I hope this helps some of you new users!