No, $300 is not a lot for car insurance. In fact, the average cost of car insurance in the United States is $1,009 per year, or about $84 per month. So if you're paying just $300 for car insurance, you're actually getting a pretty good deal.
Of course, how much you pay for car insurance depends on a number of factors, including your age, driving record, the type of car you drive and where you live. But all things being equal, $300 is definitely not a lot to pay for coverage.