What is a good idea for a story?

What is a good idea for a story?
Hi ummmm…….. well i need a good idea for a story i wrote a few but none of them work out in the end. Well thank you so much for helping me out. =D

imaginative – what is on the other side of your pillow? ideas mini monsters
how the ants got out of their farm. ideas where they went

mystery – The Way He Looked At Me . ideas a girl being stalked by this guy and kind of noticing him around a lot

romance – something starting on a beach during sunset pre climax the girl watching her man be hit on by other girls wondering if he would ever stray away since he was good looking climax being a big fight almost breaking up

essay – rural life vs city life

magical – vampires eating all the pixies (for special charge to thier powers) and pixies coming close to extinction. from pixies point of view

dont forget people put effort in for these answers if you use the make sureto chose theirs as best answer plz 🙂