Here's an innovative and cost effect solution for anyone especially kids to learn computing for around $35. Granted, depending on the amount of hardware you laying around, you''ll probably have to purchase additional components. That's best part, no heavy outlay of cash up front and if you already have a computer, you can have the RaspberryPI up and running as a web server or share files to your cell phone in not time.
"The Raspberry Pi is a credit-card-sized single-board computer developed in the UK by the Raspberry Pi Foundation with the intention of promoting the teaching of basic computer science in schools." -Wikipedia
