Way back in 1983 when I was still a kid, I read a great book–So You Want to be a Wizard, by Diane Duane. It was the story of two ordinary kids, Kit and Nita, who find out that they can do magic, and who become members of a whole planetary-wide consortium of wizardry. The wizards of Earth aren’t alone; the whole universe of sentient beings is full of wizardry. The books in the series trickled out slowly over the years, pitting Nita and Kit and a growing cast of characters against the forces of entropy, embodied by the hostile Lone Power.
The young wizards, and their older mentors, work to maintain balance by casting incredibly complex spells that are essentially magical science (no catchy Latin phrases a la Harry Potter here!), keeping the course of life in the universe going as smoothly as possible. Encountering magical cats and magical whales, traveling through space to alien planets, saving the Earth from alien attack, mentoring a race of machine beings, and more have kept the young wizards very very busy over the years. And now, more than thirty years later, the series has a hardcore group of fans, and Diane Duane has revised the earlier books to make them more technologically familiar to kids today.