How should my valentines day gift be delivered?

I am a senior in high school and I have a box of chocolates for my girlfriend. Since I go to a small private school I was thinking of grabbing one of the pre-k kids during our lunch period and having him run up with it and say happy valentines day! Would this be a good idea? or should I just give it to her myself?

If i go with the kid though how would I make sure he gives it to the right girl? She usually sits with a mix of girls and guys and since its a private school we all wear uniforms so I could not describe her cloths. I was thinking of just showing him a picture of her on my phone, pointing him in the direction of her table and hoping for the best. Any suggestions?