1. Combine peanut butter, graham cracker crumbs, and confectioners' sugar in a bowl or food processor until smooth. Refrigerate for at least 1 hour.
2. Roll teaspoonfuls of peanut butter mixture into balls. Refrigerate until ready to dip in melted chocolate.
3. Line a cookie sheet with wax paper. Melt chocolate chips and shortening together in the top of a double boiler until very liquid. Using a toothpick, dip each ball into chocolate leaving a small amount of peanut butter exposed. Place balls on the cookie sheet and refrigerate until chocolate is firm.