I understand that argument but find it very, very hard to believe in the context of primary education.
What he has learned at school in the past 6 years wouldn't fill a decent sized exercise book.
Moshe Jnr has missed loads of days of Primary School for various holidays/events and it hasn't done him any harm.
The fact that he gets hardly any meaningful homework and that we get little or no specific feedback on his progress are far more significant than a few missed days.
He'll be off on...