10-U, with the third baseman playing up and a runner on second steals should short stop cover 3rd? In general with 3rd playing up does short have responsability for 2nd and 3rd? When does 3rd cover her own base?
10U: Your intent is to get OUTS as fast as you can every chance you can, so you can't gamble as much..... You need to know your SS quickness to get to 3B to cover on a breaking runner AFTER she plays her position FIRST. Tough on a SS to read ball passing the plate (NOT put in play), then break and RACE the runner from 2B, get to the base catch and tag..... obviously we see they can do that, but its tough....
** Other option would be IF your pitcher is an excellent fielder with quickness to get to cover 3B side for bunt, let 3B SHOW Bunt coverage, then retreat on bunt to play her 3B position....... easier for catching steal to 3B, but gambling on pitcher making this play on 3B line BUNT...
IF you anticipate STEAL, OFTEN times, the batter will swing through or show bunt to slow the catcher, so throw a high pitch making it easier for the catcher to come up throwing and IF a bunt, maybe get a popup and possibly doubling up runner from 2B.
From what I have seen in most 10U's is they bunt out front of the plate. Very few can bunt down the lines. When I coached 10U we ran 1B back with no runners on, or runner on 1B, and ran 3B back with runners on 2B/3B. Seemed to work reasonably well.
The problem with the SS covering third in 10u is that you will almost never see a runner thrown out with this coverage for various reasons. Even in 'A' ball a runner caught stealing in this scenario is such a rarity. The risk/benefit is so lopsided that if this is your coverage you might opt not to even make a throw at all(not the solution).
You do have to read the bunter and consider the game situation. Often, the show bunt is just a decoy to pull the defense and move the runner. I choose to tell my catcher to field a bunt, while holding my third base back to receive a throw on the runner if the batter takes. This keeps the defense from becoming shambled and gives them control. It forces the batter to do something legitimate like lay down a good bunt and beat it out.
Now, at 10u, many girls are not expert bunters. Generally the best hitters are the teams best bunters also. This means one of 2 things if the girl is actually trying to lay down a bunt: Either she is a weaker hitter generally not capable of knocking in a runner from second, and a weaker hitter is often not a great bunter. OR, the other team is willing to let a good hitter lay down a bunt in which case you either get her out or she makes it safely without the rbi. Next batter. Remember also that at 10u if the batter gets behind in the count trying to bunt twice, they end up striking out more times than not.
I don't like to concede third to a fake bunt-er (which SS covering does), so I make the batter lay it down and beat my catcher/pitcher's arm or get behind in the count while we hold the runner. Third base covers third in case the runner steals. Seems to work based on percentages/odds.
Have SS cover third, have her cheat several steps toward third so that she has plenty of time to beat the runner ( you can't make it a foot race ). There just aren't many 10U players that can intentionally hit the ball to the area the SS should be playing on purpose to make you pay for widening the gap.
If you don't like that, I'd tell 3B to stay home and expect your pitcher to cover any bunts on the 3B side. You cannot concede the steal and allow the runner to be one passed ball away from scoring.