From charlesreid1

What Is It

What Do You Need

You need to know some Linux.

Pico CTF Learn: https://picoctf.com/learn

Notes for running CTF events: https://raw.githubusercontent.com/pwning/docs/master/suggestions-for-running-a-ctf.markdown

Who Does It

You can find capture the flag competitions for all ranges, from experts to novices. For example, here is a capture the flag for high school students:

Middle and high school students CTF: http://camsctf.com/

and a web-based capture the flag:

Christmas story hack: http://pen-testing.sans.org/holiday-challenge/2012

More story hacks:

Software

VulnHub (lots of pentesting virtual boxes): https://www.vulnhub.com/

Old software: http://www.oldapps.com/

Fun Links

PEW PEW http://ocularwarfare.com/ipew/index.html?bad_day=1&nofx=1

Elevation of Privilege card game: http://www.microsoft.com/en-us/sdl/adopt/eop.aspx

Smart Shoes ctf story: http://haxpo.nl/haxpo2015ams/ctf/

Flags