User sharelle-freshmenpresident asked: “do [Ivy League schools] take or consider IB (international baccalaureate) credits”?
In short, yes. The IB courses and tests are theoretically equivalent to AP courses and tests. However, the IB program is not as common in the United States as the AP, so admission officers will not have as much experience evaluating those scores. They will of course know what qualifies as a good score (the IB is evaluated on a scale of 1 to 7, with 7 being the highest, whereas the AP is evaluated on a scale of 1 to 5).
As for receiving credit for the results of IB examinations, this varies from school to school, just as with the AP. Some schools do give credit, whereas others only allow you to use a high IB score to place out of an equivalent course. You should check out this website to get information on how each school evaluates scores.

