The key to earthbending is utilizing neutral jing, which involves waiting and listening for the right moment to strike and, when that moment comes, acting decisively. In other words, earthbenders generally endure their enemies' attacks until the right opportunity to counterattack reveals itself.

At certain levels, unless otherwise noted, you are limited in the number of ki points you can use to cast a given spell:

Horse Stance

At 3rd level you have begun to grasp the first steps in bending the earth with your ki. You learn the Mold Earth cantrip, for you it has a range of 60 feet, and you can cast it as a bonus action.

In addition you learn to both strike out, and shield yourself with the very earth beneath you. You learn the [spell]Catapult[/spell] and Shield spells. To cast any spells from this subclass you must spend Ki points equal to spell level -1 (minimum of 1 ki point). Wisdom is your spell casting ability modifier for these spells.

Spells learned from this, and following class features do not require verbal, somatic, or material components. Instead the caster must use earth or stone, and use somatic components specific to this class. 

Tiger Stance

At 6th level, you gain further control over the earth. You gain the ability to cast the following spells: Earthbind, Maximilian's Earthen Grasp, Erupting Earth, and Stone Shape.

In addition, you gain the ability to understand the Primordial  language in particular the Terran dialect. 

Finally, you gain the ability to encase your appendages in bent earth. When attacking, the earth mould around your hands, making your unarmed strikes magical for the purposes of overcoming non-magical resistance. 

Bridge Hand Technique

Starting at level 11, you have learnt to bend with even greater amounts of earth and stone. You learn the Move Earth, Wall of Stone,  and Bones of the Earth spells. 

Your natural sensitivity with the earth has increased dramatically since you began your journey. You now possess tremor sense in a 20ft radius around you.

Praying Mantis Technique

At 17th level, you have truly become a master Earth bender. As an action, you may spend 8 ki points to cast the Earthquake spell.

Also, you gain the ability to tap into the very essence of earth. When casting any spell granted by this class sections of non-magical metal can be targeted and used instead of earth or stone.

Horse Stance

At 3rd level you have begun to grasp the first steps in bending the earth with your ki. You learn the Mold Earth cantrip, for you it has a range of 60 feet, and you can cast it as a bonus action.

In addition you learn to both strike out, and shield yourself with the very earth beneath you. You learn the [spell]Catapult[/spell] and Shield spells. To cast any spells from this subclass you must spend Ki points equal to spell level -1 (minimum of 1 ki point). Wisdom is your spell casting ability modifier for these spells.

Spells learned from this, and following class features do not require verbal, somatic, or material components. Instead the caster must use earth or stone, and use somatic components specific to this class. 

Tiger Stance

At 6th level, you gain further control over the earth. You gain the ability to cast the following spells: Earthbind, Maximilian's Earthen Grasp, Erupting Earth, and Stone Shape.

In addition, you gain the ability to understand the Primordial  language in particular the Terran dialect. 

Finally, you gain the ability to encase your appendages in bent earth. When attacking, the earth mould around your hands, making your unarmed strikes magical for the purposes of overcoming non-magical resistance. 

Bridge Hand Technique

Starting at level 11, you have learnt to bend with even greater amounts of earth and stone. You learn the Move Earth, Wall of Stone,  and Bones of the Earth spells. 

Your natural sensitivity with the earth has increased dramatically since you began your journey. You now possess tremor sense in a 20ft radius around you.

Praying Mantis Technique

At 17th level, you have truly become a master Earth bender. As an action, you may spend 8 ki points to cast the Earthquake spell.

Also, you gain the ability to tap into the very essence of earth. When casting any spell granted by this class sections of non-magical metal can be targeted and used instead of earth or stone.