As a tadpole, you wouldn't be able to tell a male from a female. Even as adults it's not an easy thing to do, and most is a matter of comapring sizes - and you wouldn't have anything to compares yours with. Some of the ways you might be able to distinguish them, are that males are more likely to call (and they're louder) than a female. Their call sounds like something rattling, a weird laugh, or a person snoring rather than a "ribbet" or croak. You can hear what they sound like in links on this website: http://allaboutfrogs.org/info/species/le… Males, especially in the spring when it's time to mate will have swollen thumbs on their front feet, and females may be plumper because of carrying eggs. So until your frog grows up, and begins to call or it lays eggs, you may not be able to tell.