It all started with a minor accident in chemistry class.
It was towards the end of the year that your teacher prepared a lab for all the students. There were synthesis items everywhere, and the students were asked to combine certain synthesis items on their lab tables to see the result.
Simple enough.
In the end, you learned that two Blaze Shards, two Frost Shards, two Thunder Shards, and four Mythril Shards make an elixer. You learned that one Blaze Gem, one Frost Gem, one Thunder Gem, and two Mythril Shards make a mega-potion. You also learned that fire and blizzard did /not/ mix well.
It was a pure accident. In a discussion about magic you were having with your lab partner about magic and the effects of it, you both began to pretend you were wizards like all immature high school juniors did. Pointing at a Frost Gem on the other side of the room, you released your hand and yelled, "Fire!" in a mocking way.
Ah, but the gods of magic seemed to disagree.
A fireball whirled out of the palm of your hand, spinning and spinning in the air as it whizzed toward the shard. The collision made a huge burst in the air, and thankfully the few students at the table were able to run off in time before the explosion. The smoke detector went off and the fire alarm blared loudly across all of Twilight Town High School, and students rushed to file out of class while you leapt for the fire extinguisher, but your fate was decided even before your heroic action.
Oh well. At least they let you finish off the last two months of the school year before expelling you.
Once your parents heard the news that you were apparently capable of having the potential of being some sort of Mage, they instantly wanted you to learn how to regulate your talent. They searched and searched for a school that would teach you combat proficiency, and the only one they found was in another world. But, they figured, it was better to move to some other foreign island, forcing you to meet new people, and graduate from high school in a place you had never even heard of before than light a building on fire.
...Right?