I work in a special needs school, with many children in wheelchairs. When the slightly milder weather comes, we wheel them into the playground or green spaces, for some fresh air. The difficulty comes when trying to put coats on children who have very limited mobility, so cant help themselves. However, if we had some knitted ponchos, that could be easily slipped over the childs head, this would make it a quicker and easier solution.
So maybe you could approach any local special needs school, and ask if they could use ponchos for the children, when they are going outdoors. A very worthwhile cause, which works really well in my school, with some very vibrant colourful patterns.