SYAG – I apologize if I misunderstood you.
You started off by writing that these kids “have trouble visualizing anything.”, not that they “can’t but that they “have trouble”.
So when you wrote: “So many of them could not, or they could only visualize an item, but not a scene.” after “we would have to teach them to visualize a scene so they could describe it. “, I thought that you meant that you had to teach them BECAUSE so many of them could not. But I guess you meant that you had to teach them, and (then realized) that “so many could not..”
Again, I apologize for misunderstanding.