She admitted sexually assaulting a two-year-old and a three-year-old between December 1, 2016, and March 11, 2018.
During the same dates, Elms also pleaded guilty to two counts of sexual assault - one against each of the youngsters - in which she intentionally indecently touched them.
Also between December 1, 2016 and March 11, 2018, it was heard that Elms committed four offences of taking indecent photographs of children.
These included two category A photographs, four category B photographs, and one category C photograph.
Between January 1st, 2016, and March 11, 2018, Elms committed six offences of distributing indecent photographs of children.
These included three category A photographs, four category B photographs, and three category C photographs.
Elms also pleaded guilty to two counts of possessing extreme pornographic images of an animal, between January 1, 2016, and March 11, 2018.
Defending Elms, Mr Chris Smyth described the case as "highly unusual", saying: "Miss Elms was only 17 herself at the time when the offences occurred".
Miss Elms was remanded in custody until her sentencing hearing.
Judge Robert Pawson said: "You have pleaded guilty to what I suspect you fully understand are extremely serious charges.
"I remand you into custody on the basis of fears for your own safety. Your sentencing will take place on January 4.
"Until that time, my strongest advice to you is that you avoid using social media for some time to come.
"You are very unlikely to make things better for your victims and their families by posting on social media, and you are very unlikely to make things better for yourself."