I recently helped a friend host a birthday party for her daughter's 7th birthday. The goal was to do as many simple/diy projects as possible. I tried to pick things that weren't intimidating. One thing we made were these pudding cups. We did this in place of ice cream and served them next to the cake. We crushed oreos and made layers of oreos and pudding. On the top I also placed a little plastic dinosaur in each and some chocolate rocks and we called it prehistoric dirt.
I also made this banner. I googled an outline for a dino skull and then just placed it over construction paper and cut out the shape. I punched out the birthday girl's names and strung them all together. I love layering banners so I also added the pompom puffs from the dollar store, and some dino punches. All for less than two bucks.
More to come, but...so far-minus some construction paper (you can grab for pennies at back to school sales in the fall), most of these has been practically free.