Secondary schools in the Hong Kong Special Administrative Region on Wednesday welcomed back groups of cross-border students for in-person classes, with parents and educators hailing the smooth operation at checkpoints but calling for more help with transportation arrangements.

Thousands of young students picked their schoolbags back up and headed to the checkpoints with their parents. They took selfies to mark the occasion and happily chatted with their peers.

Across the border, there were banners welcoming their arrival and schools held special ceremonies for their return. Some schools also sent teachers to Shenzhen, Guangdong province, to pick up the students in person.

Hong Kong and the Chinese mainland resumed full cross-boundary travel on Monday, with daily cross-border quotas and COVID-19 testing requirements dropped and all checkpoints reopened.

According to government arrangements, cross-border secondary school students returned to Hong Kong for classes from Wednesday, while kindergarten, primary and special school students will return to Hong Kong from Feb 22.

Secretary for Education Christine Choi Yuk-lin said the education bureau has been liaising with various departments on the best way to arrange for the safe, orderly and convenient return of cross-border students to Hong Kong.

She added that more than 1,000 students passed through Shenzhen Bay Port this morning and 16 special channels were opened for their passage. They can also use other e-channels. The clearance process was quite smooth, and they didn't need to wait in line.

The authorities are working hard to resume school bus services to pick up the students, and are actively following related arrangements such as for applications, licenses, drivers and insurance, Choi said.

Shun Tak Fraternal Association Yung Yau College at Tin Shui Wai in the New Territories on Wednesday welcomed back its first group of secondary school students after a three-year hiatus.

The school arranged a ceremony to mark the long-awaited gathering and for mainland and Hong Kong students to share their experiences in the past three years. It also prepared a heart-shaped card with "welcome back" remarks for students from the mainland. Choi also attended the ceremony.

Mo Kwan-ngai, father of a secondary school student at CCC Fong Yun Wah Secondary School, accompanied his daughter to the school via the Lok Ma Chau checkpoint.

"My daughter was excited to be reunited with classmates again after such a long time," he said.

Amid the pandemic, they moved to Hong Kong for the convenience of the children's schooling. As the two sides resumed normal travel, they returned to live in Shenzhen.

He added that the clearance process is relatively smooth, taking about 20 minutes. Yet the entrance is crowded as many secondary school students are accompanied by their parents. School buses have yet to be restored, and it is time-consuming to take the MTR or public buses to get to the school by themselves.

Since the border reopened fully on Monday, exhilarated travelers poured into the checkpoints, especially those at Lo Wu and Lok Ma Chau.

On both Monday and Tuesday, the control points recorded over 230,000 cross-border passengers.

Yau Chi-leung, principal of Yuen Long Merchants Association Secondary School, said on a local radio program that only a few cross-border students at his school did not return to Hong Kong on Wednesday due to personal reasons.

Ten others transferred to the Chinese mainland for study amid the pandemic, he said, adding that several students had even chosen to study at a lower grade because of concerns that they couldn't keep up with the original learning schedule.

He added that the school understands that some cross-border students were late for classes as there were few buses at the border crossings, saying it will not put pressure on them to solve this.

Wong Ching-hong, president of a parents' association representing cross-border pupils, said the biggest hurdle for students to return to Hong Kong is that they still need to declare their health situation in a mobile application and get a QR code to cross the border, whether entering or leaving the mainland.

She noted that some younger students have no mobile phones. Some parents who are busy at work also did not get a family visit permit to enter Hong Kong and can't accompany their children across the border.

She hopes the health declaration code can be scrapped or replaced with paper forms.

Wong also suggested that the government increase the number of shuttle vehicles at Lo Wu and Lok Ma Chau checkpoints, to make it more convenient for students.