The Incredibly Awesome Adventures Of Puggie Liddell, Tesla Time, Book 1 — Karen Mueller Bryson

When the wise-cracking whiz kid, Puggie Liddell's modified Gameboy activates a time travel portal, he lands in the 1890s with his sibling rival, annoyingly prissy teen sister, Gigi, who thinks history is like-totally-gross. The kids must learn to work together to find a time travel portal back to the present before the eccentric scientist, Nikola Telsa, or his arch nemesis, inventor Thomas Edison, can steal the Gameboy and use it to complete a death ray machine, an invention powerful enough to disturb the very fabric of space-time and create an instantaneous world disaster.