The origin of the word "fungo" is unknown and argued upon as there are many possible options as to the origins of this unique word. It is assumed by many to be derived from the Scottish word fung meaning to pitch, toss, or fling. This would make sense, as fungo bats are designed to do just that. Or, the alternative to this origin is that fungo comes from 1937 where David Shulman, writer for the American Speech, said, "My guess is that the word, which is baseball slang, may be explained through the elements of a compound word, fun and go." Lastly, a third belief is that the word fungo comes from an old game, similar to that of baseball, where the players used to chant, "One go, two goes, fun goes."
This is the drill we ran all through high school. It is the most time effective and skill intensive way to warm up a team, but your boys must be able to play catch! Fungo-ers stand in the "fungoe circles" that any good field has (and if it doesn't, you know where they're supposed to be - just outside of the home-plate dirt circle, towards the dugouts). The catch to this method is this - you have two first basemen, allowing both sides of the infield to throw across. Herein lies the only danger - one of the firstbasemen has a lengthy throw back to a shagger, so caution must be excersized (a catcher with a good head on his shoulders really helps).
Secondly, the first base fungo hits balls to the third baseman, who turns a double play with the second baseman to the normal first baseman, while the third base fungo hits balls to the shortstop, who throws to a shortened deep firstbaseman (this means that the deep firstbaseman stands closer to the shortstop than normal, so that the throw across this infield is the correct distance - this does NOT mean that the deep man stands any closer to the normal first base position - this length should always be sufficient)