What the hell is an IB course?
Well, since my school wanted to be a special snowflake and use IB instead of AP courses, I can explain. IB and AP are, effectively, the same thing. Teaching college or near-college level classes in high school so that you gain a college credit so that in theory you don't have to take it in college. The main difference is location, some places use IB, and others use AP.
Which sucks for me since pretty much no colleges near me recognize IB and only take AP credits so half my classes barely matter.
I went to a high school that offered both (and took some of each), and they're definitely not equivalent. The staff explicitly ranked them in terms of normal classes < AP < IB. For one, IB courses have a required peer review component-the major projects of each student get shipped off to another IB-qualified teacher somewhere in the world, which helps guard against lax standards in any particular country.
Generally what I found was that AP courses were mostly rote memorization, IB courses were mostly critical thinking. Unlike AP courses, IB does a decent job of modeling undergraduate work; they were more challenging than anything I had until I was ~5 semesters in to my BA, barring a few exceptions. It also helped that they were (for the most part, excluding a few things like Physics) two-year, so the teachers had a lot more time to work through a comprehensive curriculum instead of being forced to push test prep for the standardized bullshit at the expense of coursework.
Let's take for an example IB English. Here's how it was structured, at least for me: Two year course with an extensive reading list. The daily activity was to come to class and participate in Socratic seminar-style discussions about whatever was most recently read (the room was arranged as a very large conference room, tables ringing the outside facing inward) with zero participation from the teacher-he essentially started the class by saying "Okay, go," and then took notes on what we said and did. That was most of our grade, apart from the year-end projects. The first year we had to develop a topic relating to one of the works we'd covered, write a paper on it, and give a fifteen minute presentation for the class on it (which was also taped and shipped off to be graded).
The second year we had to write another paper on a topic of our choice, but we also had to give an on-the-spot fifteen minute lecture on a randomly assigned passage from the readings. Basically what happened there was that we walked into a room, drew an envelope from a basket of them, and pulled out our prompt, which was an unmarked passage from anywhere in anything we'd read in the past two years, with no information regarding what it was, where it was drawn from, &c. We had twenty minutes to write notes and prepare to give the talk, after which we went in to give it in a one-on-one setting with the teacher (and a tape recorder). I got lucky and drew a passage from
A Portrait of the Artist as a Young Man that I knew by heart, which made it go easy, but I'm pretty sure some of my classmates lost months off their lives from the stress there.
I took ~30-odd hours of English coursework at my undergraduate school, and only two of those courses were more educational, more challenging, or more interesting than that IB English course, and both were small and taught by senior professors who were thorough invested in the subject matter.
That said, the problem about IB credits not being recognized is very true.
So basically: If you want to skip some gen-ed courses but aren't bright/motivated enough to get into your university's honors program to skip them all, do AP courses in high school. If you want to learn real study and work skills (and maybe even enjoy your classes a little), do IB courses in high school.