Last weekend we held a birthday party for my six year old & I thought I would post my ideas & what we did & Hope these ideas help someone else :)  Invites I used Blue card stock which I glued a long (8dot) Lego to the front & two smaller sqauare Legos on the back diagonally in each corner - On the front I printed  - Calling all Brick Masters to help us celebrate Jakes 6th birthday & on the back was all the details.  Decorations We bought 30lbs of Legos which we separated by color & had in containers down the middle of children tables (which we rented)   We used the primary colors as decorations with blue, red & yellow streamers. We had red & blue table cloths & red napkins w/blue plates. I also made Lego placemats using information I had found online. The placemats had information about the history of Lego how Legos are made, including the shop drawing of a Lego, Lego fun facts online & the history of the Mini Fig.  I bought 3 Lego posters on Ebay (Agents, Coast guard & Castle) which I framed with cheap poster frames from IKEA & hung up around our patio. I also got 2 large red plastic Lego signs (like the store signs) from brinklink ($9.99 ea) & had 1 in the front yard & one hung up in the back.  I bought on Ebay a large plastic Lego Brick that I had on the cake table (our out door bar)   Activities/Games  When the children arrived it was free building for ½ hour & then lunch.   After lunch we played LEGO (bingo) with cards that we made using pictures of Lego pieces as the numbers" & we used small 1 dot Legos as the markers. We played until we had 3 winners.  Then I handed out the party favors which were Lego racers & had each child build one & then we had races (2 boy/girl heats) down the ramp my husband built. The cars that went the farthest won a small prize. We had a Legoville Pinata filled with candy & a couple of brick separators & pinata filler Party Favors/Prizes Prizes For Lego (bingo) I had mini Lego city sets (3.49 ea) & for the Races I found on ebay these cool small foam like lego bricks (like those stress relievers)   Favors Lego Race cars placemats & I was able to get (again on ebay for a $1ea) the tall Lego store cups w/lids which I handed out for there loot for the Pinata instead of bags.  Cake It was two bricks one yellow & one blue. The nubs were mini cupcakes. We were lucky & found someone to make it for us because my practice efforts did not turn out well. The lady who made the cakes said the secret was to frost them using a whipped cream based frosting or else the frosting is too stiff!  "