There are lots of versions of this in my house (!) – this is my favourite
How to make – paper plates cut in half. You can easily cut the dinosaur spikes/plates a few plates at a time. Older children who can safely use scissors can do this part themselves. 
Each dinosaur needs a tail and a head – there is a free printable here – Dinosaur Head and Tail (1) Colour these and then attach with glue.
Decorate the dinosaur with tissue paper, crayon, pens – whatever suits you. I like to give children a choice.
Decorate the pegs and attach. The dinosaur should stand up!