text2mindmap. It doesn't get much easier than this
What is it? Text 2 Mind Map is a web application that converts texts to mind maps. It takes a structured list of words or sentences, interprets it, and draws a mind map out of them. It is dead simple and can be stylized somewhat in terms of fonts and colours. You can save your mindmap as a Jpeg also.
How can I use this in the classroom? Next time you brainstorm, put away the white board marker, DOn't bother loading inspiration, you can just make a list and drop it straight in to text2mindmap.com. Your kids will nut this out in seconds. Check it out here.