Lego Block Party Birthday Party. Building a better party is super easy with our Lego Block Party Birthday theme! We have all your Lego Block Party Party Supplies, Lego Block Party Favors and Decorations that you will need to Stack up the birthday FUN!. You will find a large selection of Lego Block Party supplies all at our usual discount prices. Also be sure to check out our complete line of color coordinating solid color partyware.