The Dimensioneers — Doris Piserchia

The orphan had always known she wasn't what people described as 'normal'. Whether merely precocious or a mutant freak, she had always been able to link minds with an equally weird mutated lion and skip into the worlds of the fourth dimension.

What the heck, it sure beat staying in school on Earth - that is until she realized that some of her fellow dimension-hoppers from other planets had more in mind than just a romp in the swamp.

They were launching an inter-dimensional war of imperialism, and she alone held the secret which could save her home world - if she could only escape the truant officer long enough to pull it off!