“Stopping For School Bus On 4 Lane Highway”

I drive daily on a 4 lane highway --Hwy 10 near Orangeville (2 lanes each direction with sometimes additional turning lanes ie. 5 lanes). Rarely do I see traffic stop on the opposing side when a bus stops although there is no median. Is this correct? Do the number of lanes make a difference?

No, unless there is a median the traffic should be stopping. The number of lanes is irrelevant.