SKYRIM Teaching followers spells...100% tested.

You can teach your followers new spells via console commands on the PC version. To do so, you will first need a hexcode for the spell you want to add. 

To find out the hexcode, open up the console (by hitting the ~ key) and type in: 

help "SPELL NAME" 4 

Where SPELL NAME is the name of the spell you want your follower to have. For example, if you want your follower to be able to summon a Frost Atronach, type: 

help "conjure frost atronach" 4 

This will return several hexcode values. The ones you're looking for start with the 4-letter string "SPEL". 

In this specific case, there are 3 spells for Conjure Frost Atronach. The spells are listed from least to most powerful. The first hexcode listed for Conjure Frost Atronach is 000204C4. 

To give your follower this spell, target the follower with your mouse cursor while the console is open and type: 

addspell 000204C4 

Note : Lydia only uses spells when all other weapons she have run out of charge or has less damage than the destruction spells...however you can find her summoning atronachs and reanimating bodies...We've found Lydia healing herself while in combat...giving her the Staff of sparks or reanimation is also a good Idea..She always use it wisely and better than us..