i got a leap frog for my kids and i cant connected because avast firewall is blocking it from connecting
Not sure exactly what it is you are asking?? ???
Please provide more information. 
No answer yet?
I suppose this is Leap frog: http://www.leapfrog.com/en/get_connected/what-is-lf-connect.html
But I’m amiss how avast could prevent this device from connecting to the internet.
EDIT seems your pc connects to the internet, leapfrog connects (&synchronizes) to your pc.