The five backpacks Terrica Richardson gripped tightly against her chest sported colorful purple-and-blue designs and weighed her down with a bevy of school supplies that were stuffed in each one. There was one free bag for each of her kids, all snagged Saturday at the fifth annual Back to School Fair at the Show Place Arena in Upper Marlboro.

Richardson was one of thousands of Prince George’s County parents and students gearing up for the first day of classes for the county school system Aug. 25 by attending the fair, where families were offered free supplies, school information and even free immunizations to meet school requirements.

“The backpack is nice, but getting the right information here, ahead of time, is even better,” Richardson said.

Many parents started lining up at 6:30 a.m. for the 10 a.m. event. The goal of the fair is to ease students back into school by supporting families that can’t afford supplies and encouraging prospective students to enroll. Attendance was expected to surpass last year’s crowd of about 8,000 participants, which was up from 2013’s roughly 7,000 attendees.

Kevin M. Maxwell, the Prince George’s school system’s superintendent, greeted parents at the fair and said that the school year will start with a new strategic plan to focus more heavily on improving literacy and math skills. Maxwell said the approach, along with a focus on at-home engagement, is needed for classroom success, especially in a county plagued by lagging scores.

“We need our parents to be engaged, to help them understand what is going on in their children’s classes,” Maxwell said. “People have a lot of different perceptions of our district, but the reality is, kids can be very successful in our public school system with parents who are committed to their child’s education.”

Parents such as Richardson, who has five children in grade levels from elementary to high school, need more information to set their kids on the right path.

“Seeing the principals and teachers helps get them in the school mind-set, to think about what’s coming up,” Richardson said, also looking at booths with information on college readiness and after-school activities.

Barry Cyrus, principal of Stephen Decatur Middle School in Clinton, Md., waited in a red school polo shirt to answer questions about campus activities and the impact of changing grades.

“For many kids, transition years, from elementary to middle school or middle to high school, are really difficult,” Cyrus said. “Getting to talk to them here gives them a chance to get more familiar with how we do things. They go into the first day seeing a friendly face.”

The start of classes also marks the students’ deadlines for required immunizations for certain communicable diseases. Without them, students will not be allowed in school.

Ahmed Kpaka showed up only for the free vaccinations for his daughter, a transfer student who will be entering ninth grade.

Certain immunizations are required before the start of four grade levels: kindergarten, first, seventh and eighth.

All kindergarten students and first-graders need a varicella, or chickenpox, vaccine. The middle-school grades require vaccines to prevent tetanus, diphtheria and pertussis, or whooping cough, administered all in one shot, and a second shot for a meningococcal, or meningitis, vaccination. The requirement went into effect last year, and 400 students missed the deadline and were prevented from attending classes.

At this weekend’s fair, Angela Wakhweya said she hopes to prevent a rush at the deadline by vaccinating more than 200 students ahead of the school year. Wakhweya is a doctor and the system’s school health policy, services and innovation chief.

“Last year, we had to encourage a lot of complacent parents to get the requirement for their children,” Wakhweya said. “This year, we tried everything.”