Playing Jacks 

Euphemism for male masturbation.

Where's Johnny?
He's in the bathroom, playing jacks.

Playing Jacks by I Like Piah November 21, 2009

playing jack in the box 

sex
penis=jack, vagina=box

after the party i went over to jill's and we stayed up all night playing jack in the box

playing jack in the box by jojo548 December 16, 2008

playing jack and the beanstalk 

stimulating an erect penis until it reaches climax/cums

can be a hand job or masturbation/jerking off

jack slid up and down the bean stalk until there were clouds in the sky and the beanstalk fell limply to the ground <--playing jack and the beanstalk

playing jack and the beanstalk by jojo548 December 16, 2008

Playing Jack In The Box 

Jacking Off
The Act Of Jacking Off While Think Of A Male Friend.

Kyle Was Playing Jack In The Box While Thinking Of Dave!

Playing Jack In The Box by Claudacious September 10, 2006