The rules of Wiffle are very much like baseball. Opposing teams alternate hitting and pitching/fielding to try and get players around the bases to home base, scoring one point for each player reaching home plate. There is no running for the offensive team in wiffle, unless you are running to try and retrieve a ball that has landed in a neighbor's yard.
You can play with 3 people (1 on 1 on 1), but Wiffle is generally played with 4 or more players. There are 9 innings, with 3 outs per inning, and each batter gets 4 balls (walk) or 3 strikes (out). If the batter walks, the same player stays up and gets to keep hitting, until they are out or get a hit.
The rules of Wiffle vary from field to field. For Verbila's Field in Richmond the rules are based on the foul lines marked out and agreed upon which currently include:
Right foul line:
From home plate to the board leaning up against the fence. In right field it's the right corner of the roof of the house.
Left foul line:
From home plate to the edge of the chicken coop and a straight line to the fence beyond that. In left field it's the fence that borders the neighbor. If the ball drops in between the house and the fence it's fair.
Fair territory (base hit):
Green poles laid out in grass in front of home plate.
Double:
If you hit the house on a fly it's a double.
Triple
If you hit the roof on a fly it's a triple. That includes that little lower roof section on the left side.
Home run:
If the ball either clears the roof, or hits the roof and then rolls over the north side of the roof, it's a home run. Special note: Take note of the big pipe just to the left of the middle of the roof. That's Pipé Lopez. If you hit the ball into that pipe and it falls down into the pipe you *win the game*. No one has ever done a Pipé Lopez before.
Because we need to preserve wiffle balls, we've built in some rules that assess penalties for lost wiffle balls. If you hit the ball in the neighbor's yard you have one minute to retrieve it. If you call "distress!" within 30 seconds, your team members may assist you in retrieving the ball. If you retrieve the ball within the minute, it's a foul tip strike. If you don't get the ball within a minute, you're out.
It's generally easier to retrieve balls from the neighbor's yard beyond the left foul line (although sometimes the roof traps balls for good). The neighbor's yard on the right takes longer to get into, and is harder to negotiate. If the ball pops up behind you and goes over the fence, you can run back through the gate and get it, but it may have dropped into a mess of thorny bushes.
Note that you may bring back any wiffle ball, not necessarily the one you hit out. If you can't find yours but find another one that someone else hit out earlier, you can bring that one back and save yourself.
If your one minute has expired, but you are able to find the ball (the ball you hit) and bring it back, you are still out, but you may keep the ball on your person as a reserve ball to throw in and save yourself the next time you are in this situation.
Fielding for outs:
If the pitcher fields a ground ball cleanly, with no bobbling, while the ball is still rolling, the batter is out. If a fielder fields a ground ball cleanly, with no bobbling, while the ball is still rolling, and then throws it to the patcher, and the pitcher catches it cleanly, the batter is out. The pitcher must be on the mound when catching the ball. The pitcher cannot turn and run after a ball, but fielders can.
If there are only 2 players on the defensive team, and they choose to not place a fielder on the outfield deck, they may play balls off the deck. If a ball hits the house and then hits the deck and rolls off of it into a fielder's hands, the batter is out. If the ball is bouncing down the stairs the fielder may catch it on a bounce before it hits the ground and get the batter out.
Double play:
There are two ways to execute a doubleplay:
1. The pitcher fields the first out (cleanly!), throws it to a fielder, and the fielder throws it back to the pitcher. The pitcher must be on the mound when receiving the final throw from the fielder to get the second out. 2. A fielder fields the first out (cleanly!), throws it to the pitcher, and the pitcher throws it back to the fielder. The pitcher must be on the mound when receiving the throw from the fielder to get the second out.
Triple play:
The triple play is the same as a double play except the last player to receive a throw must immediately throw the ball toward home plate. If the ball hits the strike zone on a fly ball, they get the third out.