It is very important that you teach children how to be safe while walking on or crossing a street.
Supervision is the key.
Toddlers and preschoolers need adult supervision at all times while they are outdoors and indoors. They should never be permitted near or on a street. Look and listen for traffic to the left, then to the right and then to the left again. Cross at the street corner and walk in crosswalks if present. Keep looking while crossing the street.