I'm going to lie about my work schedule
Why would you lie about your work schedule?
I can't live without my weekend sleeps. I'll get fired if I don't lie about my work schedule. I need sleep.
You should talk to your boss about this instead of lying. Lying is wrong and it will catch up to you. Being honest is great.
How are they going to know?
They may hear about it from anyone. Just avoid lying.