I need to bunk school, to save my life!?

Iv got myself in a bit of mess. Lets just say i need to visit a clinic that doesnt open till 9am and only weekdays. I cant tell my mum, i wont bunk long. I'll go back to skl just need to sort this out, any ideas how to stop mum finding out? Would it work if i told skl that i got up late..? I live in UK btw, if that makes a difference