"The Veldt" can be read as a story about how George Hadley changes his feelings about technology. At the beginning, George thinks the nursery is the cat's meow (or the lion's roar?), but Lydia is worried about how much time the kids spend in the virtual reality Africa.
George isn't so worried. But he's getting more worried. Which is why the parents and the children start to clash over the whole "playing in Africa with human-eating lions" thing. Things are not looking good in the Hadley Household.
Remember in The Matrix how Neo had to choose whether to continue living in a machine world or break out into the real world? That's kind of George's situation too.
He started out liking the nursery (and the whole house). Then he became a little more worried about it when his kids talked back to him. So now, at the climax of the story, he has to make a big ol' decision: live it up in the Smart House or shut it all down?
Now, you might want to say that the lion attack is the most exciting part of the story. We totally agree. So why isn't that the climax? Well, we like to think of the climax as the point when someone faces some major decision.
Unfortunately, this decision means it's the house and the kids against George and Lydia, which leads to…
After George makes his decision, the kids and the nursery defeat George and Lydia. (But at least George made a choice, right?)
George and Lydia may be lion chow, but the real kick in the pants is that the kids have also made their choice. As David said they would, they chose the nursery over their real parents.
Notice how David finds them? The lions and the kids are both eating. Creepy. In this moment, we're reminded of just how close the kids are to their gadgets. We sympathize, because we only eat while our iPods are charging. Otherwise, our hands are busy scrolling.