Ann Maguire, 61, was killed in her classroom at Corpus Christi Catholic college in the Halton Moor area of east Leeds on Monday morning.
Described on Tuesday as an "amazing, inspirational teacher" who was an "asset to the city", she had worked at the school for 40 years and was due to retire at the end of the summer term, the chair of governors said.
A 15-year-old boy from the school was arrested after being restrained by teachers and remains in custody. He is to be questioned by detectives later on Tuesday, West Yorkshire police said.
The boy was too "traumatised" to be formally interviewed on Monday in the aftermath of the attack, a police source said.
At a special service held in the church next to the school on Tuesday, priests offered prayers not just for Maguire's family but also that of her attacker.
Police confirmed on Tuesday that Corpus Christi had
a dedicated "safer schools" officer stationed in the school, tasked with keeping pupils and staff safe, but that she was elsewhere when the attack took place.
"She wasn't in the school at the time of this incident – some of the safer schools officers support a number of schools across the city. This officer partners with another school and unfortunately she was helping that school at the time of this incident," said chief inspector Nik Adams, head of neighbourhood policing in the area.
At a press conference outside the school on Tuesday, DS Simon Beldon, of West Yorkshire police, said the teenage suspect would be questioned by officers "at some point during today".
It would not be a quick process, he warned: "Given his young age, this is a process which needs to be handled very sensitively, and may take some time to complete.
"The pupils who witnessed this incident are still being interviewed by specialist officers who are very experienced in dealing with child witnesses and will ensure that their safety is paramount."
Asked if he was any clearer on what motivated the attack or nearer to understanding what exactly happened, Beldon said: "It's very early days in what we are trying to achieve, so I really don't want to speculate on that."
A crime scene remained in place in the area of the school where the murder took place, said Beldon, but it was "no longer actively under forensic examination".
Maguire's death is thought to be the first time a teacher has been stabbed to death in a British classroom, and the first killing of a teacher in a school since the 1996 Dunblane massacre.
Police have confirmed she was stabbed in front of terrified pupils, who raised the alarm. Educational psychologists were on hand to help those affected, as well as trained counsellors from Catholic Care, said Nigel Richardson, Leeds city council's director of children's services.
Martin Dowling, chair of governors at Corpus Christi, said Maguire had recently gone down to a four-day week in preparation for her retirement at the end of the school year.
He said: "Ann was a wonderful and dedicated teacher and will be remembered fondly by all of us. She had taught at Corpus Christi for 40 years and touched the lives of many people in the local community. She also taught the parents of some of our pupils.
"I would also like to pay tribute to the staff and students for the way they have coped with these tragic events."
Paying tribute to Maguire, Richardson told reporters: "Our thoughts and sympathies are with Ann's family, friends and colleagues at this difficult time.
"Ann was an amazing, inspirational teacher, and a pillar of the local community and a real asset to the city of Leeds."
He said it was the right decision to keep the school open so the community could come together to support one another.
In a statement, school head Steve Mort said: "Our whole school community remains in shock today.
"Ann Maguire was a long-serving, highly-regarded and much-loved member of staff and our thoughts and prayers are with her family at this time.
"She will be sadly missed by colleagues, current and former pupils, and the community as a whole. Our school is open today and we have specialist support available for students and staff if they feel that they need it, which will continue for as long as required."
Neighbourhood officer Adams paid tribute to all the staff and pupils for coming into school the day after the attack.
He said: "This is an horrific incident. It's unprecedented nationally but very much in this local community it's something which has caused a great deal of shock and distress, as you can imagine.
"This is very much an isolated incident. This is not part of a wider problem that exists locally here."
At a service in the Corpus Christi church next door to the school on Tuesday morning, former pupils across the age ranges joined together to pray for Maguire.
Monsignor Paul Fisher led prayers for all affected by the tragedy.
He said: "Today we pray for the light of hope. Hope for ourselves that we will come to terms, eventually, with what has happened.
"We pray for all those young people at our school next door and their teachers. We pray for Ann's family and friends. We pray for Ann.
"We offer prayers too for the family of the man who, unfortunately, did what he did. We pray for ourselves."
After the service, several generations of former pupils paid tribute to Maguire.
Laying flowers outside the school gates on Tuesday, actor Jim Millea, 55, said he remembered Maguire starting at Corpus Christi in the 1970s fresh out of teacher training college.
Millea went on to appear in Emmerdale after leaving the school and said Maguire took an interest in his career long after he had left. "She said to me how well I was doing and always took an interest," he said.
"She was warm, approachable and very human, really. You could tell she was in the right place."
Becky Simmons, 19, shared fond memories of a "long running battle" she'd waged with Maguire over her hair colour. "I started dyeing it from year 9 but it was only in year 11 when Mrs Maguire was my head of year that I really started to get in trouble," she said. "I remember her publicly telling me off for coming in with a bright pink fringe and my hair bright purple at the back and she had to put me in isolation for three days but privately she told me: 'Don't tell anyone but I quite like it.' She was so lovely."
Culled from TheGuardian
Follow us On Twitter
2. Kim Kardashian & Kanye West planning THREE Ceremonies!
3. Special Photos: Tiwa and Teebillz get ready to tie the knot tomorrow in Dubai
4. PHOTOS: Stunning bride: Tiwa Savage.
5. Photos from Alvan Ikoku's son's wedding
6. Official photos from Ohimai Amaize and Tessy Oliseh's wedding