My daughter's preschool has a large indoor playspace, so she's still getting lots of playtime!
But my son's elementary school has two outdoor playgrounds, and only one of them is accessible (basically only the blacktop area). It's had a big impact on his enjoyment of school, and perhaps also his ability to concentrate during the day, We're also running around a lot less on weekends too.
Are your kids getting less playtime this winter?