Helianthus annuus

Completely safe, the seeds are a snack, and the ASPCA lists it as non-toxic to pets.
Young sunflowers turn to follow the sun across the sky all day, then swing back east overnight to be ready for sunrise.
This one is genuinely harmless to people. Still look with your eyes and let it go about its day.
Always ask a grown-up before you touch any animal or plant. If something bites or stings you, tell an adult right away.
Source: ASPCA
Read more about the sunflower at Wikipedia.