Here are some of the things I made for my son's 5th birthday party.
I made a hot lava rock to play hot potato with. Made from glued together pieces of syrofoam that i shaped with a knife (great for getting out any aggression) and painted. I don't have a picture of the final product. Sorry!
The party hats inspired by hats I saw online (can't remember the site I saw them on). Bought poster board at the 99cent store and used elastic string.
I made a papier mache volcano from an old lamp shade and did the old science class formula of baking soda and vinegar.
I cut feet shapes out of colored craft foam for them to wear and let the "dino stomp" on a sheet of bubble wrap. Bad picture.
Pin the tail on the dino. I can't take credit for this lovely dinosaur, my brother made this one for me.
The cake tasted horrible but it looked awesome. It was way overcooked and frosting from a can. Oh well, kids don't care.
I also papier mache eggs from water balloons and buried dog bones in the sand box for an excavation site. I have no pictures of these.
Thanks for looking, I hope this helps inspire a dino party of your own. I'll try to find some of the sites that inspired me.