I definitely think that even middle and high school students can appreciate the poetry of Wordsworth, Coleridge, and Emerson. Nature seems to be somewhat of a dying escape in the current technological filled world we live in... so I don't know how well most students will relate to the sublime scenes being described within this poetry but I think one activity to maybe try before introducing this kind of content is to assign students to write about one of the most beautiful spaces they've been in and how they felt in that space.
This could also be a good opportunity to collaborate with a science teacher and take a field trip out into nature. I remember distinctively in middle school that my English teacher and my science teacher teamed up and had us go on a field trip to a watershed where salmon were mating/spawning. While we were out there, we were asked to observe as both scientists and as poets. We wrote 10 WOW lines and we were supposed to revolve them around our five senses: touch, taste, smell, sight, and sound. I don't think any of us had any taste lines but we had plenty to see, smell, touch, and hear.
Looking back, I am almost disappointed that my English teacher didn't take that opportunity to share some older poetry written about nature. Even though we were working on composing our own poems and then illustrating them (somewhat... the assignment was to write two poems, one about the journey of the salmon and the other about our own journey and then, on a paper cut-out of a salmon, we were supposed to draw five to ten things from each of our poems), it could have been just a brief aside to offer us inspiration for our own poems.
Students can gain from making connections between their own experiences and the experiences of those who came before them. If we allow students to write their own poetry, which would be—unbeknownst to them—a mimic of romantic, transcendent poetry, and then we share poems like Resolution and Independence, Each and All, or This Lime-tree Bower my Prison with them... I believe they will see on their own how they had a similar experience while out observing and trying to capture nature in words. I think we sometimes limit children by thinking this stuff is too far over their heads. I hope to someday teach a lesson like this and be floored by the students' writing afterward.
It might be a good idea to experiment on how much a difference it makes in the project whether the poetry is read just before the field trip or student writing as opposed to reading it after. I like the idea of after because I feel like students will be more free with their writing if they don't feel like they're expected to write a certain way and then we can see the organic similarities we all have in our encounters within nature.