This three-part command block contraption allows you to cast spells in Minecraft 1.9 with no mods!
First, you're going to need to place three command blocks, spacing them out at least five blocks apart along the z-axis. Next, paste the three commands in this post into those command blocks. If you're running a version prior to 15w41a, use the link marked "Riding"; if you're running a version after that point, use the link marked "Passengers".

To complete the installation of the contraptions, simply power the three command blocks!

Next: How to cast the spells. For each altar, you'll need an enchanting table and a specific block which you'll drop on top of the placed enchanting table.

• Fire: netherrack. Enables spells Fire, Lava, and Xplode.
  
• Water: ice. Enables spells Water, Storm, and Nature.
  
• Air: wool. Enables spells Air, Storm, and Xplode.
  
• Earth: dirt. Enables spells Earth, Lava, and Nature.
  

Standing by an altar will enable you to cast that altar's spells, but disable the other spells.
To cast a spell you've built the altar for, just type /trigger ____ add #. You have to have enough XP to pay!
There are three levels for each of the primary spells, and two for each of the secondary spells.

• Fire:
  1. Ignus - Sets that block on fire
     
  2. Incendio - Lights the nearest mob on fire
     
  3. Inferno - Lights all nearby mobs and players on fire
     
  
  
• Water:
  1. Aguamenti - Sets the weather to rain and places a block of water
     
  2. Hailstorm - Bats fly around making amazing ice sculptures and trapping mobs
     
  3. Glacius - All nearby mobs and players get frozen in ice blocks
     
  
  
• Air:
  1. Levicorpus - Lets you fly around for ten seconds before safely landing
     
  2. Distract - Summons a diversion and lets you sneak away
     
  3. Levicorpus Maxima - Throws all nearby mobs and players skyward
     
  
  
• Earth
  1. Protego - Give yourself resistance and other effects
     
  2. Quicksand - Traps all nearby mobs and players in a pit of quicksand
     
  3. Entomb - Boulders fall on nearby mobs and players
     
  
  
• Lava
  1. Vulcus - A pit of lava opens, sentencing anything standing there to a quick death
     
  2. Meteor Shower - Five giant fireballs fall from the sky
     
  
  
• Storm
  1. Thunderclap - Strikes the nearest mob with a lightning bolt
     
  2. Tempest - Annihalates all mobs and players in the vicinity with lightning
     
  
  
• Xplode
  1. Reducto - Blows up whatever obstacle - or enemy - is in your way
     
  2. Pompeii - Everything's pretty much dead
     
  
  
• Nature
  1. Herbos - Encourages plants to grow quickly
     
  2. Devil's Snare - All nearby mobs are swallowed by giant trees
     
  
  

Now that I'm done explaining, here's how to get the commands!

Command 1: The Altars
Riding: http://pastebin.com/LsSqNduz
Passengers: http://pastebin.com/XWQXeSvD

Command 2: Primary Spells
Riding: Not currently available
Passengers: http://pastebin.com/BiMbsYnY

Command 3: Secondary Spells
Riding: Not currently available
Passengers: http://pastebin.com/43Mj6e6H