How often (or at all) do you replace your Magic Circles? Do they lose firmness or structure as time goes on?

yes, I think all props get worn out - unfortunately! They are not environmentally friendly! :0(  But less resistant rings are still good to have for those who may not be as strong. Maybe you could tie ribbons around the old/new ones so students could "see" the level of resistance right away. (Like how weights and resistance bands are often colored for ease of use)

Thank you for your response, Maggie!  GREAT ideas!!