I declare shenanagins
A loud accusation you make when someone did something sneaky, and you want everyone to know about it. You probably yell it so loud that the whole school hears it.
I declare shenanagins! You told my crush I was a total disaster!
I declare shenanagins! You took my lunch and gave me a sandwich made of dirt!
I declare shenanagins! You said I was the worst at drawing!