So, as a consultant you would be 1099 I assume. So you have to pay both half's of social security. Also, what you earn will be deducted from your social security. There are rules on that.....check into it. I think it only hits the month you get paid by them.
I am basing my answer on the Google range of 85 to 125 for that job.
Look at your old salary and turn it into an hourly rate. Double it and round up to the next 100. Then keep rounding up to a minimum of 200 per hour. 250 sounds better to me.
And they pay you for prep time to build the class. And your travel time.
And you tell them what days. None of this Monday, Wednesday, Friday crap. It's days in a row so your time off isn't all chopped up.
Otherwise, tell them they can blow you.