How do I stop my stomach from growling during cl?

I always eat a big breakfast (I kinda force myself to... I don't really want to) but my stomach always seems to growl during cl. It's REALLY embarring. I can't just take out food and start eating during cl, one of my teachers (5th period... when it's the worst) doesn't allow food OR water during cl. I try pushing books against my stomach, slouching, making noise other than that, whatever, but it doesn't really help. Anything I can do? Thanks :)