"Elevii mănâncă prânzul la ora doisprezece."

Translation: The students eat the lunch at twelve.

[RalphBeato]

What about "The students eat lunch at noon" ? As I recall a similar translation in a previous lesson marked it as correct.

[Gekokujo]

Why not "have lunch"?

[pablopublico]

What about "The students eat the lunch at twelve hours"? Is it not idiomatic?