My one-time 'Story of the Day' nomination, "Lying to Melissa" by John Benson, features a preteen boy (11) manipulating his babysitter into spanking him, possibly more than he expected.
Since you asked, I did find quite a few of my own stories with the theme of a child or young adult attempting to get him/herself spanked by a pretty female, for one reason or another.
Almost all of them are F/M, F/m, F/b, f/m, f/b, g/b etc., based on my spankophile orientation:
"Next Time"
"A Promise is a Promise"
"Eavesdropping, Peeping and Asking Nicely"/"Incorrigible"/'Paybacks and Payoffs" [story trilogy]
(All of these involve the same boyish spankee, who's quite 'bottomish' and manipulative--I know that the mother-daughter relationships are different in the trilogy than in the earlier account.)
"The Middlegirl" (Short--multiple characters manipulating one another)
"Clandestine Cybernaut" (Short--lesbian lovers online)
"Showing Them" (Teenaged boy trying to impress his female cousins)
"Hit Girls" (Preteen boys wanting attention from older sisters)
"Philip's Favorite Babysitter" (Preteen boy learns a long-lasting lesson)
"The Way of the Will" (College boy paddled by sorority girls)
Until I checked my story listings, I hadn't realized how much I'd employed this theme myself...

--C.K.