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Along with the information in the title, I can provide a few more details. I read this in the early to mid-nineties, and the cover art had a teenage boy who had his hands on his head with a few stylized "BZZZAP" onomatopoeia around his head.
My memory of the plot is hazy, but it dealt with a computer-savvy teenager who accidentally electrocuted himself while working on his computer. He found that he was able to easily ace his tests at school (specifically a math exam) because of this. I'm not sure if he was able to interface with internet, or if that's something I imagined he would be able to do while I was reading the book.