The bracelet or ring is worn on the body. I think a collection of these could be shared between schools, regions, or even countries – they’d just need a wash in-between. These bracelets and their technology remain fun if each student only wears them for a limited period of time. Some options include: a particular 2-week period when all the students in the school wear bracelets (as a follow-up to some WASH educational training), having a bracelet move between students as a reward for a good behavior for the last week, and competition/collaboration between groups of students to see what % of time their bracelets changed. The pigment/colorant in the bracelet or ring changes color when exposed to the pH of the soap as an elementary student. The elementary student wears the jewelry, but the information about it being exposed to soap is seen by everyone – teachers, family members, peers, etc.