Another great way is using PrePaid cards found in convenience stores. You can basically get a prepaird $25 Visa Gift Card, enter it through PayPal and it will be accepted.
More Information:
http://usa.visa.com/personal/cards/prep ... d_how.html
Good luck and with this, I don't understand how no one can buy stuff on the internet, including kids. (Unless of course, they have no money)