Got a dog?
Get one of those dog whistles from the pet store that farmers use. Humans can't hear them so when you whistle it a dog will hear it (and hopefully come) and humans won't. Good luck.
That was some else's answer, im doing my project on how different types of music affect a dog's pulse, in this way i sort of learn how dog's hear certain pitches, but yes, somehow involve the whistle in that too if yoy'd like... just sort of an idea.... believe me i understand, i have had to do quite a few science fair projects myself :)
=D =P =)
~Emily~