A classroom assistant who carried out a five-month campaign of bullying against a seven-year-old pupil that included taping her to a chair and shutting her in a storeroom has been given a community order, including a requirement to do 40 hours of unpaid work.

Rachael Regan, 43, singled out and bullied the girl at a school in the Calderdale area of West Yorkshire.

Regan’s trial last month was told about a catalogue of incidents against the pupil, who is now nine, which included sticking Post-it notes to her thumbs, tying her shoes on with string, calling her a nickname, goading her with a biscuit, hiding her doll and tearing up her photograph.

Judge Neil Davey QC at Bradford crown court criticised the length of time the classroom assistant had been on bail before she was charged, while the Crown Prosecution Service decided what to do. He said this wait was a punishment in itself, explaining that this was why he had not considered a prison sentence.

Regan, of Illingworth, West Yorkshire, was found guilty of child cruelty after the trial, which finished last month.

A teacher colleague, Deborah McDonald, 41, was cleared of the same offence.

Davey said to her: “You have been convicted by a jury of cruelty to a small child, in effect of bullying her to the extent that it would properly be described as cruelty.”

He said her conduct had been shameful and a breach of trust. “You breached that trust by turning her into a figure of fun,” he said.

Davey said Regan had invited others to ridicule the girl when she taped her to a chair. He said the defendant had already lost the job she loved and would be barred from working with children. “You humiliated [the girl], you’ve already been professionally humiliated, now you’ve been publicly humiliated,” he said.

But the judge said the girl had recovered from her ordeal and was “back to her old happy, bubbly, extrovert self”.

Davey pointed out that the allegations were made in January 2013 but Regan was not charged until last April. He told her this period of legal limbo was substantial punishment as she lived for months with the uncertainly of not knowing whether she would eventually face prison.

Simon Waley, prosecuting, told the week-long trial last year that an investigation was launched by the school and the police after the girl told her mother a teacher had tied her to a chair with sticky tape so she could not move.

He said: “She said that the class had been laughing at her and that she was the ‘class clown’.” Waley said: “She said that Mrs Regan put it all around the chair and it was hard breathing. She said that she couldn’t get out to reach her things. She said that the whole class were laughing.”

The girl’s mother said the moment her daughter told her a teaching assistant had taped her to a chair was heartbreaking.

The woman, who cannot be named for legal reasons, told the jury the girl clung to her “for dear life” with tears streaming down her face after the incident.

Waley told the trial that the girl also said to police that Regan had bound string to her legs and feet to keep her pumps on, and that Regan put Post-it notes on to her thumbs when she had been sucking them and shut the door to a storeroom, leaving her on a chair inside.

Other staff members at the school told police they had witnessed some of the incidents. One support assistant said the girl’s arms were “fastened down by her sides with the Sellotape around her more than once” and said she was taped to the chair for about 10 minutes.

She said Regan went to another classroom to fetch another teaching assistant to show her what she had done. Waley said Regan told her colleague: “She’ll not get up and wander around the classroom now.” He said Regan pulled a photograph of the girl off the wall and ripped it to pieces in front of her.

The court heard that the defendants denied bullying the girl when interviewed by the police and described some of the incidents as “fun” and “a joke”.

Regan refused to answer questions on Thursday as she left court with a friend.