So lots of people are working from home and their kids are home from school. My wife and I are lucky because we both are able to work from home and trade off duties taking care of our 4 year old.
I thought our schedule would be helpful for other families as a model. YMMV.
7am Breakfast
8am Independent work like flash cards, practice writing, workbooks
9:30am Creative time like coloring, drawing, building toys (blocks, legos), crafts
11am Outdoor playtime. (So far we've mostly walked around the neighborhood)
12pm Lunch
1pm Rest time / Quiet Time / Possibly Nap
2pm More independent work
3:30pm Pick up / Chores appropriate for a 4 year old
4pm Free play, puzzles, reading to him, etc
5pm Dinner and normal nighttime routine
This is aspirational and subject to change. Any thoughts on what you're doing is welcome.