Everybody in our street know the new collection day.
Everybody in our street knows the new collection day.✓Richtige Antwort
Everybody in our street are checking the notice.
Everybody in our street have received a leaflet.
Erklärung
Everybody takes singular agreement, so knows is the correct present form with that subject. Know and have treat everybody as plural, while are also conflicts with the pronoun's grammatical singularity.