请教大家车保险一次事故都都保到$300,000那么高吗？有没有办法短期改变保额.否则当不了儿子班上活动义务司机

For the 1st time, I requested to be a volunteer driver for my son's field trip. He is in 1st grade. The teacher gave me a form to fill out. I noticed that the vehicle must be insured for at least split limit coverage of $100,000 bodily injury and liability $300,000 per occurance and $50,000 property damage. I checked my insurance policy and found I am not qualified.
My vehicle only covers $50,000 bodily injury and liability $100,000 per occurance. My vehicle coverage has been like that for 10 years.

Is there a way that I can adjust my insurance for a month and reverse back afterwards?

Thank you very much.