There are a number of programming languages that range in difficulty to learn so MIT developed Scratch as a programming language for 8 – 16 year olds that makes it easier to create interactive stories, animations, games, music, and art.
You can download Scratch from here and get started – you can explore combining it with sensors to make your scratch projects sense and respond to things outside your computer.
You can get help from Scratch support or visit the Scratch wiki
If you are an educator and want to use Scratch in your classes – visit ScratchED and join a growing community of educators using Scratch.