Julie Morris, 44, the safeguarding lead at a school in Wigan, and David Morris filmed themselves abusing and raping a girl under the age of 13.
The teacher, of Hindley, was jailed at Liverpool Crown Court for 13 years.
Her 52-year-old partner, of St Helens, admitted 34 offences at a previous hearing and was jailed for 16 years.
Julie Morris worked at St George’s Central C of E Primary School in Wigan but the charges are not related to her employment.
The court heard the videos showed Julie Morris, of Hindley, giggling as the abuse took place.
The Crown Prosecution Service said it was one of the most horrific cases they have had to deal with.
“It truly appears like both of them were equally involved,” district crown prosecutor Damion Lloyd said.
“They’ve formed this horrendous sexual interest in children and they’ve acted out their most unpleasant fantasies on the victim.
“It feels like the relationship between them is just a self-feeding cycle where they have effectively driven each other on to worse and worse acts.”
In his 20 years of prosecuting, he said it was the “pinnacle” of the most “disgusting and depraved types of acts that people can discuss and do”.
The charges:
Julie Morris admitted two counts of rape, nine of inciting a child under the age of 13 to engage in sexual activity and two of engaging in sexual activity in the presence of a child.
She also admitted three counts of taking indecent images of a child, one of engaging in sexual communication with a child and one of possessing indecent images of a child.
David Morris admitted seven counts of rape, 13 counts of causing or inciting a child under 13 to engage in sexual activity, and two counts of engaging in sexual activity in the presence of a child.
He also pleaded guilty to taking indecent images, of categories A, B and C, possessing and distributing indecent images and two counts of engaging in sexual communications with a child.
He also admitted three counts of voyeurism, possession of an extreme pornographic image and possession of a prohibited image of a child.