Are There No Free Sites To Find Pen Pals For Kids?

My son uses www.studentsoftheworld.info and he says it works for him.

This isn't really an answer but totally

Not sure but I am looking for pen pal for my daughter age 8 and my son age 14.

Yes there are free pen pals websites. I am giving you a few web links for your study and convenience.

www.interpals.net
www.associatedcontent.com
www.efriends.pnet.pl

There are some websites where you can find pen pals for kids and that are specially made for children and teens so you check this website where you can find pen pals for kids.
www.studentsoftheworld.infomenu_penpals.php3