1) Recognize that some days will be easier and some days will be harder and this is all normal. We live in uncertain times and are all anxious and grieving. In this abnormal situation, anger is normal and anxiety is normal. Learn to ride the wave of the emotions and realize that they are ok. It is a time for compassion not only to those we care about but to ourselves as well. You will lose your cool and that is ok, but find some time to calm down, be empathic, and give the hug.
2) Keep in mind that children will pick up on parent's emotional state. Where possible, it is worthwhile and important for to engage in their own self care (reaching out to others, exercise, hobbies). Calmer parents make calmer children and although full calmness is not possible, every step is a plus.
3) Try to keep as much structure as possible. No matter what children may say, they need predictability and regularity. They should be getting dressed and follow routines, even if the routines are somewhat relaxed and flexible. Setting general times for schoolwork and recreation is wise (and there will be exceptions to this too).
4) Try to do family bonding and remain positive. Cook and bake together, play games, use art and humor, listen to music, clean, make family albums, etc. Despite the additional responsibilities alluded to in your letter (which are all true), we are home more. We do save some time on traveling, less hours in school, and less simchas and communal/social events.
5) Finally, allow children to express feelings. Ask them how they are doing and encourage them to draw or write. Have occasional heart to heart talks if they are open to it. They may need to release pent up emotions.
May Hashem continue to provide us with an extra dose of strength during these unusual times.