Nearly of the school-age pedestrians killed in school bus related crashes were between five and seven years old.

Nearly 1/2 of the school-age pedestrians killed in school bus related crashes were between five and seven years old.
Children within these groups tend to still haven't developed a perfect mechanism to fully observe their surrounding. Which make them often cross the streets without paying attention to the vehicles near them.

You can literally find this on google of each science career and search up what type of training you need and how many years in school