1st Birthday ABC Blocks Birthday Party. ABC's and 1 2 3"s, cake, party hats and building blocks...we make building a birthday party super easy with our ABC Blocks Party Birthday theme! We have all your 1st Birthday Blocks Party Supplies and Decorations that you will need to Stack up the birthday FUN!. You will find a large selection of ABC Blocks Party supplies all at our usual discount prices. Also be sure to check out our complete line of color coordinating solid color partyware like Bermuda Blue, Pumpkin Spice and Mimosa.