"The reason I'm offering the lessons is to give the boys, some of whom have special educational needs, something to boost their self-esteem" Well, fair enough then.
That one's Sindarin. However you can learn Quenya on line.
This blog written in Klingon, possibly created using this translation program.
But let's ramp this thing up a notch: this site offers details of over 300 made up languages.
Bogomol is used by the insectoid race of Epsilon Indi II. The designer describes it as a "quantum language": the meaning of an utterance remains only potential until the very end, when a "ranking syllable" collapses all the potential meanings into one.