I think most of the educational value is gained from having access to a microscope, not having each child able to build one. A teacher who builds one in class w

I think most of the educational value is gained from having access to a microscope, not having each child able to build one. A teacher who builds one in class with the kids watching and then selects a useful slide and projects it on a wall will likely get you 95% of the benefit. "Look at this unboiled water vs this boiled water". I didn't have to build my microscope at school but it was still educational to have access to one. This is primarily for kids that don't have what we had. (At least from an educational perspective - the medical perspective is arguably more important.)