Hiya! So glad I found you on here:). Great ideas! Love the seed idea! Love the grove. BUT from teaching experience it is far too much for 20 minutes. When I prepaired lessons I would write down what I really wanted to get across - normally looong list - then you have to do something I hated called "didactic reduction". Thinking of the age I would go for impressions. When you where your lovely new cloak it will look great. You are a bard - why not telling them a story that druids need to go to school just like them, that in the old days it was twenty odd years (sorry, just starting the course
), about the bards, druids, ovates, love to nature, the symbol of the oak leave. Keep it veeeery basic and simple. Should you get through that really fast, then have something in mind like the meditation to use the time propely to the end.
I only worked in german schools - so maybe english pupils are just much more disciplined and organized, but in my experience you need some time to get the focused already - so effective instead of 20min left with even less. BUT - I dont know how it works in a UK school
Love and light, Luna x