Looking at some of the negative posts, you really have to wonder what some people do for fun....
I was lucky enough to see the film during its all-too-brief theatrical run. The audience laughed its heads off. I'm watching a tape of it as I type and it's still dang funny!
It's also got a sweet side, with unexpected turns of genuine pathos. The late, great Royal Dano is especially effective as the lonely, down-on-his-luck farmer Wrenchmuller. Ariana Richards and J.J. Anderson are great as the lead kids. And the actors in the Martian suits, although limited to mime, do a great job
Another thing to look for is the background details. The film is full of homages, pastiches, and references to other SF and fantasy films. Take a look at the Martian costumes next time. One of them is wearing a Marty McFly costume, another is a Ghostbuster, a third is in a House Atreides uniform, and a fourth is wearing a Last Starfighter flightsuit.

Antonioni, by making this film, had assumed the role of Papa Smurf to all the little long-haired, American, radical student-Smurfs. He had taken them under the guiding protection of his European communist wings, showing appreciation and support for their confused American ways. (These Smurfs are red and wear blue, not the other way around.) The radical Smurfs were happy to get the guidance of a wise old man with gray hair who regularly preys to the God of all long-haired Smurfs, Lenin the Communist - another wise old man whose beard made the Smurfs take him even more seriously, for it symbolized something wise, though they did not quite know why they regarded the beard to have this kind of deep effect on them. Castro, another wise bearded man, has often profited from this confusion and exuded magical powers with his beard over his naive overseas admirers. (Not to mention Che Guevara: that beard has a certain je-ne-sais-pas-quoi about it, makes one want to immediately embrace Marx and his lovely, pacifistic teachings) The film starts with a muddled meeting of radically stupid radical students, who engage in dialogues that truly redefine the word "confused". As confused as a blind-folded dog falling of a high-story building into a bottomless pit. Suddenly, the movie's "hero" (well, Antonioni's hero) rises up and says something to his pathetic left-wing peers and then leaves, hoping that this display of "mega-coolness" will improve his James Dean image and vastly increase his chances of getting laid with the best "chicks" in the next mass hippie orgy. Eventually he gets into trouble with cops (i.e. pigs) at a rally, and spends the movie under the blue American capitalist skies, looking for freedom Or something like that.
Antonioni's predictable assault on capitalism is not only intellectually hollow, but has (or had) nothing new to offer; it's just the same old trigger-happy one-dimensional cops, businessmen discussing business deals (and what's wrong with that, isn't that how Antonioni's movies get made?), and endless shots of TV commercials and billboards advertising the oh-so morally decadent products for the abhorrent, selfish, and greedy right-wing rabble-population who thinks of no one but themselves, their families, their work, and their children.
Papa Smurf Antonioni, just like his long-haired Smurfs and Smurfettes of the late 60s, failed to notice the most obvious and vital aspect about their silly movement: they were allowed to have their laughable meetings and express their anti-establishment opinions freely within that very establishment, whereas the students in those countries whose left-wing systems they admired, did not (and still do not). By far the greatest irony about the hippies - and Antonioni, naturally, failed to realize this as well (his judgment being clouded by cocaine-snorting and an excessive intake of LSD) - is that hippies were (are) the garbage-residue of capitalism. This is an incredible irony. Only in a successfully-functioning capitalist system can you find that species called "hippie"; a spoiled, ungrateful, and selfish bunch of middle and upper-middle class losers.
The film itself seems to go on forever. Antonioni takes his sweet time with getting on with it, while including overlong scenes of pointlessness, with a high dullness factor. His attempts at symbolism are annoying and trite. His statements are highly dubious, at best. This film is Antonioni's way of saying that violent revolution is the solution. And this is what we get from an old, saturated, filthy-rich, fat film-maker who lives in villas and dines in the best French and Italian restaurants.
I don't remember seeing any major Western movie about the Tiananmen massacre of thousands of students in China. But when one Western student gets shot for waving Che Guevara's face into all our faces, we get ten major films about it at once. I suppose this means that a Chinese life is worth a thousand times less than a Western one  at least to the left-wing hypocrites who infest movies.
If you're a Marxist neo-hippy and disliked this awful review, please klick "NO" below.