Do you speed up, or do you slow down?

As you come up to an intersection, and you see the traffic light turn yellow, do you speed up or do you slow down? Sometimes it's a bit dangerous because there are cars trying to make a left turn. Note that this is north american way of driving because we left turn into traffic.
When I am all by myself, I usually speed up. But, when I am with my family, specially with my kids, I make a conscious effort to slow down.
How about you? Do you speed up lead foot? Or do you slow down grandpa?