I thought you did a great job with some of the techniques....
The titles were totally appropriate though unfortunately a bit on the long side (I realise this was needed to fit with the excellent choice of music, but I can't see any way around this other than change the music or have more characters
)
The shots themselves were pretty good, swapping vetween views to show what was going on (guy reading the instructions etc). I wasn't so sure abour the need for the "on the other side" caption .... and I was even less sure about the choice of font... maybe if the titles had been in that font then....
The flight of the boomerang both through the air and approaching/hitting the other guy was very good - that speeded up, jerky footage was exactly what was required and the sound effect was great. The quality on YT wasn't that great so I couldn't see, did you edit the boomerang on as an overlay?
Altogether a great attempt - and not a bad little story to experiment with the techniques.