Looks like two of those three examples are nodes that were imported from GNIS a long time ago. In my experience it’s pretty common for features that were imported from GNIS as nodes to have later been mapped as a polygon, but the mapper forgot to merge/delete the redundant node.
I think it’s a great idea to combine these redundant nodes and areas together, in the spirit of One feature, one OSM element. I’ve created some MapRoulette challenges in the past for doing similar work on parks and reservoirs. I believe this is the Overpass query I used to create the parks challenge, in case it’s useful:
[timeout:3600]
[maxsize:4294967296]
;
// WARNING: this query takes a long time to run
rel(id:148838); // USA
map_to_area;
(
wr[leisure = park][name](area);
wr[leisure = nature_reserve][name](area);
wr[boundary = protected_area][name](area);
) -> .park_areas;
foreach.park_areas -> .park_area (
node[leisure = park][name](around.park_area: 250);
node._
(if: t["name"] == park_area.set(t["name"]))
;
Edit: @Minh_Nguyen beat me to it on the GNIS connection, and makes a good point about amenity=school
vs landuse=eductation
. I’m not an expert on school tagging so I’ll leave it to others to figure out what the right tags are for these situations, but I endorse the idea of merging redundant features together where possible.