Restraining Line
The farthest an attacking player can legally "Push Up" without being "Offside". See "Offside Rule (Simplified)" for the definition. For example, Anson Dorrance plays an aggressive style of attack and has said that when his opponent has the ball, he likes to have his Forwards play on the edge of the restraining line.
Law 13 - Free Kicks
On a direct kick you can score by kicking the ball directly into the goal. On an indirect kick you cannot score directly.
Shape and Balance
Working on shape and balance is something that many coaches like to talk about but many don't actually seem to know how to actually train teams to work on this.
