They really should have a couple of these at every school. I got mine as a requested birthday present and I've been playing day after day. I always wanted to learn programming but never knew where to start. After using the drag-and-drop programming system for a couple weeks, I've now started to learn Java so I can try something more complex.
Fun: 5/5 - Could something be funnier than designing, building and programming a robot?
Educational: 5/5 - As stated above, this is about designing, building and programming robots.
Durable: 5/5 I've got it a couple weeks ago, but in my 15 years of existence I haven't seen a single broken lego in my house.
Overall: 5/5 Ladies and gentlemen, we're talking about THE PERFECT TOY here.
Little kids: If your kids play with LEGO, they can also program a Mindstorm. Period.
Teenagers: As in my case, the perfect bridge to start learning a real programming language.
Adults: If you already know a programming language, this is going to be the best purchase of your life.
Teachers: Spread the word of LEGO Mindstorms to your pupils. They'll thank you.
If I had the money, I would buy thousands of these. Thousands.