Dozens of public schools across Baltimore changed the bell schedule for the fall prompting backlash from parents and some members of the community.

Many parents, students and teachers took to social media to express their outrage after the school system announced changes in early June.

Sandrene Smith is a parent of students at both City Neighbors Charter School and Baltimore Polytechnic Institute which are kindergarten through 8th grade and high school respectively. But neither of her children are eligible for school bus transportation services.

Both her children are supposed to start classes at 8 a.m. which means she’s unable to pick them up at the same time when they get out at 2:50 p.m. starting on August 29.

“I'm gonna have to pick him (her son) up from school early, in order to shoot 25 minutes to get to my daughter's school, to pick her up on time, '' Smith said.

School officials blame the school bus driver shortage, which is happening nationwide, as the primary reason.

About 80% of bus drivers are contractors, not employees of the school district but the system looks to hire more as internal employees.

Baltimore City Public Schools hired consultants to analyze the school bus system last year who suggested that drivers were not being efficient. Drivers were unable to pick up and drop off students swiftly because school start and end times were too similar and most of the buses were used once a day.

There were more than 77,800 students enrolled across 155 schools in the Baltimore city public school system last year.

Last year, 6,200 students were assigned to ride yellow school buses and a small group of students were offered van and cab services.

Those students eligible for school bus service had either individual education plans, are attending pre-kindergarten, are experiencing homelessness or live more than a mile and a half away from school. If students are ineligible they may get rides or take the Maryland Transit Authority buses.

Even though Baltimore parent Smith’s daughter is attending high school, she doesn’t think it’s safe for her to take public transportation to class.

More than 1,000 students eligible for school bus pick up and drop off didn’t have a bus route nearby their homes. During the year some students eventually had access to a school bus but 300 students had no dedicated transportation to and from school.

And that’s not good enough, said Lynette Washington, Chief Operations Office for Baltimore City Public Schools.

“We have to get all of our children to school, and accommodate all children that have transportation service needs,” Washington said.

About 44% of school schedules won’t change this year, according to the district.

But there are 93 schools across the district which will have new bell schedules.

About 40% of those schools will open 15 minutes earlier, according to a WYPR data analysis.

Roughly 10% of schools will open 30 minutes earlier and nearly 9% will start at least 45 minutes earlier, the data shows.

Nearly 27% of schools will open 15 minutes later and 13% will open 30 minutes later or more.

District officials said they gave parents plenty of time to adjust their commute and address concerns by announcing the changes this summer but expect to have a plan to further support families by the start of the school year.

But Washington, the school official, said that giving parents more time to digest the changes would have been helpful.

Smith, the local parent, said that the school system did not include parents in the decision and that they do not value parents' input. She worries how the new schedule will affect her kids.

“I really don't want my students to fail because of lack of sleep or to not make it to school on time,” she said. “This throws off the whole dynamic of my household.”

The ideal start time for a school is between 8 a.m. and 8:30 a.m., said Amy Wolfson, adolescent sleep health researcher and professor of psychology at Loyola University Maryland.

That’s because school-aged children and adolescents need a minimum of 8 and a half hours of sleep.

Wolfson said research shows that adolescents need more time than younger children because many experience a phenomenon known as Circadian Phase Delay.

“What that basically means is one's actual biological clock tells the adolescent that they're sleepy or ready to fall asleep later in the evening and waking up later in the morning, then prior to the onset of puberty,” Wolfson said.

Later school start times are an overall benefit for teenagers, she said. It can lead to improved academic performance and a decrease in mental health problems, absenteeism, tardiness, car accidents and injuries.

Wolfson noted that studies show that later start times do not lead to students staying up later. She said it allows students to return to their natural schedule.

“We're actually asking teenagers to do something like, take calculus at 7:35 in the morning when we, as adults would never, could never do our best at any job at that hour,” Wolfson said.

Baltimore city school officials considered sleep health research, especially for outcomes with high school students, but ultimately the school system had to make a “difficult decision.”