We had a WDW themed party for my DD's 1st birthday in July. Here are some ideas for you:
Invitations: We created an invitation on the computer with DD's picture and party information, printed it out, and added character stickers to make it Disneyish. (Disneyish: is that a word?

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Decorations: We decorated with WDW park maps, postcards, streamers e.t.c. (Plus, my dad is an artist and he created a Buzz Lightyear poster and an Eeyore poster for pin the tail on the donkey.

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Food: I love your idea of using Mickey pasta! What you could do is make enough regular spaghetti to feed everyone. Then make a bag (or box) or two of Mickey pasta. Combine them together and while people are eating, they can look for the "Hidden Mickeys" in the pasta! (Maybe you can even have a WDW themed prize for the person who finds the most Hidden Mickeys in their pasta!)
Thank you cards: For our thank you cards, we sent a WDW postcard. That helped us save on postage and we kept with the theme! (By the way, I didn't think of this idea while we were in WDW so, I had to buy a lot of 20 WDW postcards off of eBay for $4.00)
Favors: For favors, you can make chocolate suckers from Mickey molds, put them in a clear, plastic bag, tie them with a red ribbon, and put a thank you poem on them from your DD. (You can use Avery labels to type out the poem and stick them on the bag.)
If you plan on favors for any children that might be coming, you can put Mickey juice pouches, Mickey fruit snacks, Mickey or Pooh cookies e.t.c. in bags. You can then set aside any leftover juice pouches, fruit snacks, or cookies for your DD as snacks when you go to WDW!
That is all I can think of for now. When we had our DD's 1st birthday party in July, we had 20 children and 50 adults attend. So, a lot of our WDW themeing came in on the games and prizes. If you would like ideas on those, please let me know and I will share that with you as well. If you have any questions, feel free to post here or PM....
Hope you have a wonderful party and a wonderful trip to WDW!
