Any explanation for using "dans" as opposed to "à"?
"La rue" is a semi-closed space (houses on both sides), hence the use of "dans la rue".
"La route" is an open space (no houses or only a few), hence the use of "sur la route".
The French always use the preposition dans when saying "in / on the street" → "dans la rue ".
Why is votre rue wrong?
If you don't give your whole sentence, we can't tell.
Why is entendu masculine if the girl is the one who heard the wolf? Does it agree with the object instead of the subject?
The auxiliary is "avoir". Only with the auxiliary "être" does the past participle agree with the subject.