The below explanation comes straight from US Youth Soccer:

1. Because we want our young soccer players to touch the soccer ball more often and become more skillful with it! (Individual technical development)

2. Because we want our young soccer players to make more, less-complicated decisions during the game! (Tactical development)

3. Because we want our young soccer players to be more physically efficient in the field space they are playing in! (Reduced field size)

4. Because we want our young soccer players to have more individual teaching time with the coach! Less players on the field and less players on the team will guarantee this! (Need to feel worthy and need to feel important)

5. Because we want our young soccer players to have more, involved playing time in the game! (More opportunity to solve problems that only the game presents)

6. Because we want our young soccer players to have more opportunity to play on both sides of the ball! (More exposure to attacking and defending situations)

7. Because we want our young soccer players to have more opportunities to score goals! (Pure excitement)

These are the reasons why we adults must foster "Small-Sided Games" in our youth soccer programs. The "Small-Sided" environment is a developmentally appropriate environment for our young soccer players. It's a FUN environment that focuses on the young soccer player.

There are some specific differences that are important to note:

• U5 players (birth year 2013) will play 3v3
• U9 & U10 (birth year 2009 & 2008) will play 7v7
• U11 & U12 (birth year 2007 & 2006) will play 9v9
• Slide tackling will be allowed only at U9 and above
• Keepers are allowed to punt the ball at U11 and above
• U9 & U10 fields will include a build out line (more information below)
• All field sizes will be smaller then previous season

First, It's important to know that the build out line ONLY APPLIES TO U9 & U10 teams.  These teams are 2009 & 2008 birth years and play 7v7.

The Build out line is used to promote playing the ball in an unpressured setting.  The bottom line is that when the goal keeper has the ball, the opposing team needs to move behind the build-out line, NOT pressure the goal keeper.

• Goal Keepers may not punt the ball.  They can pass (kick the ball on the ground to another player), throw, or roll the ball.
• Once the ball has left the Goal Keepers possession, it is in play and the opposing team may cross the build-out line.  If it is a goal-kick, the ball must leave the penalty area before it is considered out of the Goal Keepers possession.
• A defending team player may be in front of the build out line when the ball is played (if the goal keeper chooses to not wait), but if they interfere in anyway with play before the ball crosses the build out line (as determined by the referee), the opposing team is awarded an indirect free kick.
• If a Goal Keeper punts the ball, the defending team is awarded an indirect free kick from the spot of the offense.  Teach your Goal Keeper NO PUNTING.
• If the defending team passes the build out line before the ball has left the Goal Keepers possession, the opposing team is awarded an indirect free kick from the point of the infraction (at the build-out line).
• Players can only be penalized for an offside offense if they are between the build out line and the goal line.  There is no offsides between the build out line and the halfway line.