Jump On It

Just a couple seconds ago, I was upstairs texting my friends. They wanted to go to Color Me Mine this weekend. I turned to my dad.
"Dad, are we doing anything this weekend?"
"I don't know," he replied.
"Yes we are!' Eric jumped in. "We are going to...um...Jump on It!"
"Yeah, Jump on It!" Emma crowed.
Laney, apparently immersed turning a lamp on and off, looked up, completely bewildered, and asked with extreme innocence and cuteness: "Jump on what?"