None…don’t even go there. A 40 year old divorcee is not interested. Trust me, been there. She gets plenty of male attention from her own peers. She is not looking for a fling with a 21 year old to make her feel young or desirable. I found myself at that time having to explain this to young guys…(I’m good. I don’t need your “generosity”…but thanks for thinking of an old lady;)
Assuming you just like her or hit it off on an emotional level, then out of respect for her, just walk away. This would be very embarrassing for her. And it would be disrespecting her position in your past life. No one wants people to spread rumors about them and a former student out at IHOP Saturday night…