I know someone who did it.
She was coming back after cancer and only wanted to work part time. However, she was also a self-congessed control freak and couldn't bear not to be in full charge of her class's basic skills.
As luck would have it, another younger teacher at the school was simultaneously considering asking for a leave of absence to pursue some artistic activities.
They joined forces and offred the school a job share - my friend in the mornings doing all the literacy, phonics, guided reading, handwriting, maths and science. The other teacher did the non-core subjects every afternoon. The mornings were longer than the afternoons (something for you to check carefully, OP) but they still preferred it that way, and did it for 5 years in the end.
The school relaxed into it, and were happy for them to arrange things between them eg one of them having a long weekend away, or one going on a course or even Christmas shopping while the other just stayed for the day, as well as covering for one another's illness if they could.
Things to check:
Is the morning the same length as an afternoon?
Will you have a heavier marking load? If so, is there anything that can be done to offset?
Will you be expected to stay on for staff merting after school (even 50% of the time)?
In the end, the school can say this is the only part time scenario they can offer, but you might find it works for you.