Whenever she gets mad or very determined about something, Sadie kicks her back legs. I know all dogs do this sometimes, but she always does it when she's upset about something. When the alarm goes off in the morning, if I don't get up right away, she goes to the end of the bed and starts kicking to let me know we need to get up. If there's a toy in her toy box that she can't get to or if it's under another toy that she just doesn't want to move, she kicks so I know to come over there & get it for her. I'm always asking her what she's throwing a tantrum about.
OTher things she does:
1) lift her leg to pee
2) play hide & seek
3) when she wants to push my buttons to see what she can get away with before I get mad, she'll start scratching the back cushions on my couch. She'll not turn her head, but cut her eyes over to me to see if I'm watching. She's just like a kid trying to see what she can get away with!