* What is a producer?
* What is a herbivore?
* What is a carnivore?
* What is an omnivore?
* What is a scavenger?
Use the search engine, and dinosaur sites, and rainforest sites, as well as look in books.
* What is a food chain?
* What is a food web?
You will find useful information here, and on this site. Now you need to roughly sketch out a food web for the photographer to do a good copy of for the slideshow.