Devin,

The leaves, like all parts of a cannabis plant, have some THC. The buds, on the other hand, are LOADED with THC. The whole purpose of growing cannabis is to bring the plant to maturity and harvest the buds. Leaves are necessary for photosynthesis, which is how the plant converts light into energy for growth. Cutting off the leaves for smoke will harm your plant. You'll get a short, crappy high.... and then a headache.

Have some patience and self control, it will pay off in the end.