My daughter screamed "I'M AWAAAAAKE!!!" every morning for three years. One day after telling her (like always) that she can just come and quietly let us know, she finally listened.
Same! We got one of those clocks that change colors during a programmable time frame, so if she wakes up and it's still red, she knows it's time to go back to sleep. Yellow means almost time to get up, and green means it's after 6am. It helped a lot, but we still get the occasionally bizarre 3am protests.