Playing devil's advocate here, which subjects would you remove in order to accommodate these classes? You propose 3 new items for grades 1-4. Here is my son's (3rd grade) schedule...
Citizenship
Language Arts
Mathematics
Reading
Science
Spelling
Social Studies
The below subjects are in 2 groups and rotate daily, so today he may have Art and World Language, tomorrow he'll have Music and PE.
Art
World Language (Spanish)
Music
P.E.
Now, Indiana already mandates a 180 day school year, and Perry Township has already moved to a "balanced calendar". His day starts at 7:55am and ends at 3:40pm.
No eliminations. Citizenship and Social studies could include Constitutional and US History.
PE can include safety. Little kids can start with air soft look a likes or BB guns.
I'm not proposing it be an every day, one class period event. It can and should be incorporated into a normal schedule. The is a lot of fluff in the Curriculums today. I'm sure they could find things that could be either shortened or dropped in lieu of something important like this.