"Ni kune rigardas la knabojn."
Translation:Together we are looking at the boys.
Is this supposed to mean a lot of people watch a lot of boys? Seems sketch overall.
I don't see any problem about it (although I'm no native). If it sounds OK to you, yet was marked wrong, you should report it.
It seems to me that in this context "look at" is the better translation, since "watch" can have other connotations in this context.
I'm guessing this verb works the same way as regarder in French as it means "to look /at/"?
Not really, theres no indication here that only two people are watching. That would more likely be "ni ambaŭ rigardas"