The younger kids can still be carriers and infect their grandparents
Hence the mockery :)
Now, the next thing to consider is the relevance of school as it now stands and how this move is essentially priming for virtual schooling, which will be far cheaper and further degrade results for those who are unable to afford direct contact. Luckily, most of the young kids today won't have the possibility to work anyway....
🎼 Always Look On The Bright Side Of Life