What technology in "The Veldt" suggests a futuristic setting, how does the nursery work, and is it functioning properly in the story?
In "The Veldt," the Happylife Home cleans itself, bathes the children, sings the children to sleep, and produces dinners that emerge from the dining table—all futuristic technology. The nursery has viewscreens on all four walls, and the children program the screens according to their wishes. The nursery is supposed to "catch the telepathic emanations" of the children's minds and "fulfill their every desire."
The nursery is not working properly in that, although it is following the children's wishes to murder their parents, it has crossed the line between fantasy and reality by allowing the lions to actually eat the parents. According to George, the viewscreens are supposed to be "crystal walls, that's all ... supersensitive color film." It would be one thing to show the parents being eaten by the lions on the viewscreens as a form of fantasy, but to have it physically happen seems to be a design flaw. Further, if the premise behind the Happylife Home is to create a happy family, the nursery in fact divides the family by usurping the role of the parents and allowing the children to become alienated from the adults.
There are many examples of technology which suggest a futuristic setting. The entire house is equipped with devices that did not exist at the time the story was written, and many of which do not exist today. The house does everything for the family: makes all meals completely automatically, bathes & dresses everyone, even rocks them to sleep. In fact, it works so well that Lydia feels completely useless as a wife and mother. This prompts the idea for a "vacation": turning off the house & doing everything for themselves.
The nursery is the prime example of cutting-edge technology. The machine works through telepathy. It reads a person’s thoughts, then projects them onto the walls to create the environment. Anything you imagine can come to life in the room. It does function properly at first, but soon only responds to the children. As the children's thoughts become more sinister, it somehow feeds on them and brings their creations to life, with horrific consequences for their parents.