For my son's 3rd birthday I did a Bob the Builder/Construction party.  For his invitations I made them using bright orange cardstock, folded them in half and then cut them into squares. I drew a black line along the outside edge of the sign and then turned it so it would look like a diamond and wrote in the middle "Construction Site Ahead"  On the inside I wrote "Foreman (child's name) is turning 3!  Come to our construction site at (your address) to help us celebrate! (Date of party) is dynamite! Your shift will start at 1 and end at 3. Please call Project Mananger (parent's name) to order your lunch. I also included with the invitation a little lunch menu of different types of sandwhiches that they could order.   For decorations, I went to the local Home Depot and got some Caution tape and used it like streamers. I also got orange and black streamers, orange and black balloons and orange silverware. At my local party store, I went and got Bob the Builder plates, cups, and napkins.  For the food, I had already put together the sandwhich that everyone had ordered and using a wrench cookie cutter, I cut the bread, meat or whatever they were having on their sandwhich and they had wrench shaped sandwhiches, along with some tool shaped gummy snacks, graham crackers (because they look like wood) and a drink. I put all their lunches in brown paper sacks with their names on it. For the cake, I made it look like a construction site. I made a marble cake and in one corner of the cake I dug a little hole out and piled the cake I dug out next to the hole and put one of the Bob the Builder trucks by it. I used crushed up oreo cookies and made a road going across the cake and used green frosting as the grassy area on the cake. I had other trucks on the cake from Bob the Builder and a Bob the Builder figure on the cake too. I also made a jello giggler with blue jello and made it kind of oval shaped. I kind of dug out some of the cake and put the giggler in the little hole so it looked like a pond.  I also made brownies since some people in our families don't like cake. I cut the brownies up into squares and piled them into the back of one of my son's big tonka trucks that I cleaned REALLY good. I also put crushed up oreo cookies all over them to make them look more like a pile of dirt and placed a few gummy worms in the "pile of dirt" also. As the guests arrived, they were given a yellow construction hat with their name on it and also asked to 'sign in for their shift'. Which I had a clip board with some paper that looked like blue prints and had everyone write a birthday wish for the birthday boy.  (I later put this in his scrapbook.) For games we did a bag toss game where I had the kids try to throw a bean bag I made with some gray material (to look like a rock) and some dry beans. Whoever got the most 'rocks' into the back of a truck, won a prize.  We also did place the hat on Bob game.  (like pin the tail on the donkey). Then I also set up a little obstacle course in my back yard and split the kids up into two teams.  Which ever team had everyone push a tonka truck around this obstacle course won. Even though they all got prizes anyway. And as they were all leaving, I gave out the goodie bags which I filled with Bob the Builder stickers, a small thing of bubbles, truck pez despenser with a package of pez and more tool shaped gummy snacks.  A few days after his party, we sent out thank you notes to everyone that looked like another construction sign and said 'Thanks for helping us get the job done!"