I think that the answer varies a LOT according to the individual classroom teacher (and school curriculum committee) and their pedagogical philosophy.
Some teachers REALLY believe in seat-work, some believe in repetition and 'skill-building' with a pencil and crayons and markers and scissors and glue, some believe in a lot of physical large-motor activities and interactive learning...
and some of them really believe that it's not the way to teach most children at this age for developmental reasons.
I'd say that the sum total probably ranges from 30-40 minutes a day to as much as 2.5 HOURS a day in those grades. It's very dependent on the local culture.