The Agoge was a spartan training facility in which young boys were trained to be men. They were whipped and beaten,and taught to never show pain. They were taught to fight,to steal, and if necessary,to kill. When they turn 18, they became reserve members of the spartan army.
The most commonly used formation of the spartans was the Phalanx. They fight as a single,impenetrable unit. A Spartan's shield protects the man to his left from foot to neck. If there is a weakpoint the whole phalanx collapses. This for mation can be used to win a battle in which the numbers are heavily against you. A fine example is the 300 spartans taking on thousands of persians (yes it was real).
Spartans are extremly skilled fighters on thier own,and even stronger together.
Armor- Spartans wore bronze chestplates,greaves,and helmets. They are most famous for thier large bronze shields.
Weapons- Every Spartan carries a spear and a 2 foot short sword.