What your geology class teaches is true. Plus, most plates are right now moving away from each other (unless your point of reference is on the opposite side of the planet when considering two plates' motion). You would actually have to spend ridiculously high amounts of energy to start pushing them back. Not to mention huge tsunamis, earthquakes, the risk of magnetic reversal, extreme volcanic and orogenic events and whatnot.
And in the end you will have all the landmass together. There is little chance that we would have retained all our scientific progress due to the severely severe calamities that would befall. Plus, in the end the climatic conditions far inland would be extreme. Summers would be scorching while winters would freeze the bones to the core. Plus, very little rainfall in the innermost reaches of this new aggregated landmass.
All in all, don't think about it.
And if you must do that, just wait out and all continents would eventually meet up again. It is going to take up a tremendously long time though.
Nothing else is going to help you much.