Book about a boy who travels to a parallel universe to get a book

Question

I can't remember the gender of the main character.

I remember bits and pieces from different books, but I think they're all part of the same series. The pieces may not be in order or from multiple books.

1. Boy somehow ends up in a mirror universe that's darker and seems to have no people. He has to travel to a certain office(?) building and steal a book. I think this is towards the end of the book (I can't remember the events leading up to it). I think he finds the portal in a forest or something behind his school.

2. He goes into the ocean with mermaids or something and has to save the ocean from pollution.

3. Aliens exist and are observing Earth, because they think it's undeveloped and are waiting for them to be advanced enough.

4. His mother ends up in hospital and he does something to save her.

5. He goes to Ireland(?) and enters a mountain or something to find a race of people. I can't remember who showed him how, but I'm pretty sure she used magic.

6. He goes to Mars and saves a race from war with themselves(?). This place was hidden inside an illusion. He's also grouped with a linguist that learned their language.

7. He travels to another world where there's a prince. I can't remember, but I think it might've been part of a tournament.

8. His sister goes to a robot planet through a portal. I think the actual planet was a robot/AI and had lots of little robots on it. Can't remember what happens here, but he goes there and saves her from something.

It was set a few years ago, when computers weren't common (his family got one early in the first book, I think).

Thanks in advance if someone finds it.

Answer 1

This is Diane Duane's Young Wizards series. The main characters are Kit and Nita, who get roped into becoming wizards, people empowered by The Powers That Be to fight against the Lone Power, who embodies entropy.

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Boy somehow ends up in a mirror universe that's darker and seems to have no people. He has to travel to a certain office(?) building and steal a book. I think this is towards the end of the book (I can't remember the events leading up to it). I think he finds the portal in a forest or something behind his school.

So You Want to be a Wizard - Kit and Nina travel to an alternate world where the Lone Power reigns to steal "The Book of Night with Moon" and relight the sun.

He goes into the ocean with mermaids or something and has to save the ocean from pollution.

I think you're referring to Deep Wizardry, where Kit and Nina travel with whales. It's a magical ritual, though.

Aliens exist and are observing Earth, because they think it's undeveloped and are waiting for them to be advanced enough.

Aliens show up in several books in the series, so I'm not entirely sure on this one.

His mother ends up in hospital and he does something to save her.

The Wizard's Dilemna

He goes to Ireland(?) and enters a mountain or something to find a race of people. I can't remember who showed him how, but I'm pretty sure she used magic.

A Wizard Abroad

He goes to Mars and saves a race from war with themselves(?). This place was hidden inside an illusion. He's also grouped with a linguist that learned their language.

Possible A Wizard of Mars. I haven't read that one yet. I vaguely recall Wizard's Holiday involving an illusion on another world, but it's been a while.

He travels to another world where there's a prince. I can't remember, but I think it might've been part of a tournament.

Sorry. No clue on that one.

His sister goes to a robot planet through a portal. I think the actual planet was a robot/AI and had lots of little robots on it. Can't remember what happens here, but he goes there and saves her from something.

High Wizardry. It's actually Nita's little sister, Dairine.

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It was set a few years ago, when computers weren't common (his family got one early in the first book, I think).

It's a running joke among fans of the series to point out that the technology advances incredibly fast in-series, as the third book introduces the spell computer as a state-of-the-art Apple computer (with no bite out of the apple on the logo) that's recognizable as 1980s technology, and the current books have spellbooks on iPods, all apparently in the space of a few years in-universe.

Answer 2

A number of the references to "he" above should be "she." Nita (Juanita) Callahan is the main character in most of the plots. Her friend Kit (Christopher) Rodriguez is second, and her younger sister Dairine. All of them are wizards.

1. Nita and Kit go together to a dark alternate New York City to retrieve the Book of Night With Moon in the first book of the series, So You Want to Be a Wizard.

2. Nita is the primary protagonist undersea in Deep Wizardry. The issue of ocean pollution is secondary there, but appears in later stories in the series, too. There are no mermaids. Nita and Kit are transformed into whales through different magical means, and their companions are wizardly whales.

3. It is Nita's mother who is stricken with cancer in A Wizard Alone.

4. It is Nita who travels to Ireland in A Wizard Abroad.

5. Kit is the one most interested in Mars in A Wizard of Mars. He and Nita, together with other wizards, save the culture at war with itself.

6. Dairine, Nita's younger sister, grows close to Roshaun, a crown prince and wizard with the skill to perform magic to manage solar flares in A Wizard's Holiday, and the relationship continues in Wizards at War.

7. This is the story of Dairine's initiation into wizardry in High Wizardry.

The series has been updated recently to more current computer technology.