From my own experience, both learning and teaching, I would like to suggest the following tips (generally during the first apprentice games, but also during the first full games). I would even suggest modifying the "Let Them Play" section of the "How To Teach Mage Wars" guide to at least suggest these tips if the teacher thinks it will help their particular group of apprentices.
1) Use a short time limit for the first few games. The first games should be just long enough to get 3-5 turns. Later games could be 30, 45, or 60 minutes. Perhaps until "first Mage blood", or use "60 minutes -- most damage done to opponent Mage wins".
REASON: It takes several games to see how opening decisions affect the game, and how important they are. New players won’t be able to do the mana-math for their initial spells or plan their early board positions until they've played a few games. Getting through more openings faster will give them enough opening strategy skill to enjoy the full game.
MY EXPERIENCE: If your first game takes 2 hours, and half way through you realize you totally screwed up in the first 15 minutes, then you're wasting a lot of time and not having much fun while you wait for your opponent to kill you. I've seen some completely unrecoverable mistakes in the first 2 rounds of a 2 hour game -- that player was so frustrated that they have yet to try Mage Wars again.
2) Employ the "It's okay this time, but from now on, you know the rule" Rule. It's hard for new players to choose spells effectively, and sometimes they make mistakes because they are not fully aware of all the rules.
MY EXPERIENCE: I had a player (his 2nd game) attempt to play a second Bear Strength on one of his creatures late in the round. It was not practical to rewind the whole round and let them choose a new spell. Instead, we came up with something fair for this particular casting. We chose to move Bear Strength to another friendly target that happened to be in the same zone. Other options would be: a) let them do it this time, or b) let them swap for some other buffing enchantment and place that on the original target instead.
REASON: The Planning Phase requires experience that new players just don't have at first. Mistakes will be made, e.g. they plan some great attack only to find out they can't hit incorporeal creatures the same way. Rather than slap them in the face with a rule they haven't master yet, let it go. It'll be more fun, and the game will keep moving.
Combining Tip #1 (which keeps the game short and makes it clear it's a "tutorial" game) and Tip #2 (which teaches instead of punishes) for the first couple (short) games will help new players have more fun and learn faster.
