Jan Steyn addressed mourners at the River of Life Family Church in Vanderbijlpark during the funeral service of his 14-year-old son, Jandré Steyn.

"I feel the pain inside me. Let us pray for our children who are no longer with us. It is time to pray for our children. God's son is with us as parents too. You understand our pain and we understand your pain," he said.

Pastor Armand Niemand described Jandré as an energetic and brave boy who loved fishing, rugby and athletics.

Mourners watched a slideshow of Jandré as a baby and through his childhood, including when he represented the school in rugby and athletics.

"February 1, was his last day on earth. He lost his life at his school. We should not be angry with the Lord. We must look at this tragedy with a different eye. We ask ourselves many questions. God will heal our heavy hearts. God is with the deceased and injured children. God can make beauty out of ashes.

"Let's open our hearts and look at this tragedy in another way. This is a national tragedy, it has touched many people," said Niemand.

Jandré, Roydon Olckers and Marli Currie were killed after a concrete slab above a corridor at the school crashed onto 26 pupils on February 1. Over the weekend another pupil, Marnus Nagel, succumbed to his injuries while in hospital.

Steyn added that they were also praying for the injured children who were still in hospital.

"They are with the Lord and we are happy that some of them are making progress. I want to thank members of the media for their professionalism and how they have handled their stories. Thank you very much for your support," he said through tears.

Gauteng department of education spokesperson Steve Mabona said 12 pupils were still receiving medical attention at various hospitals while others had been discharged and were recuperating at home.

Jandré's body was cremated with only his immediate family in attendance.

Roydon's father, Donovan Olckers, who was also present, told News24 that he attended Jandré's funeral to offer support to the family.

"Tomorrow I am bidding farewell to my son," he said.

The funeral services for Roydon, Manus and Marli will take place at various locations in Vanderbijlpark on Friday.

Following the incident, Gauteng MEC for education Panyaza Lesufi shut down the school, limiting access to parts of the school for teachers and pupils. The school is expected to reopen fully on Monday after structural analysis of the building by engineers.

Tents to be used as classrooms were erected in the school yard on Thursday.