Lots of educators are using Scratch to teach elementary students animated computer programming. Scratch is a free programming language developed by the Lifelong Kindergarten at MIT's Media Lab. I think Scratch is an amazing tool, but being an engineer, I like when you can add a hands-on component to essentially a virtual environment. The folks at SparkFun have developed the PicoBoard, which can add an element of sensor control to students' animated creations.
A few months ago, I bought a PicoBoard from SparkFun (only $35.96 with your educator discount). I'll admit that it was a bit tricky getting my computer to recognize it the first time (I needed an FTDI driver), but SparkFun has posted a wealth of online resources to help get your device up and running. My favorite 3 sensors are the slider, sound sensor, and light sensor. A really simple way to get started is to write a script to simply scale your sprite (animated character) based on the sensor value. For example, in the script shown above, when you put your finger over the light sensor (blocking out the light), the sprite shrinks, but when you shine a flashlight onto the sensor, the sprite becomes really large. Note that this script was written using the older version of Scratch (v1.4). I used it, because you can download this software directly onto your computer. SparkFun has a plug-in that you can add if you are using the online version of Scratch (v2.0).