Pick’s Theorem

Is there a way to prove Pick’s Theorem for beginners (meaning no calculus etc)?
My teacher talked about it yesterday. 
@RZ923 That's a very good question! I never learned the proof, but I believe it involves induction. You can more easily prove that Pick's Theorem works for simple shapes like triangles and rectangles. Using these smaller shapes, you create any polygon whose vertices lie on lattice points (points with integer coordinates). Sorry that I don't know the proof right now, but I'll try to look into it someday!