You’re still in Texas, right, @tmorgan? Does Texas do Next Gen Science Standards? If so, I would think you could align 3D prints of trilobites with 3-LS4-1 Biological Evolution: Unity and Diversity (http://www.nextgenscience.org/pe/3-ls4-1-biological-evolution-unity-and-diversity) especially if you were able to make a few different species, so the class could talk about how different species of trilobites filled different niches and had different features.
Students could probably use the specific types of software to create their own species, too, then talk about their roles in your classroom ecology. @cgrant would be able to speak more about using the specific software (and I think she’s posted a few things about it elsewhere in this 3D fossils forum!)