first visualization: low-income vs. high-income schooling
One of my favorite things about this visualization is how responsive it is. Everything moves and changes as you move over it to show that the data is changing at the top. It's also cool that it's color coded by country so that it packs even more information in without having to write more or repeat information. One of the things that makes me question this data is that there a bunch of missing countries, including all of North America. Most Western countries are missing, so it's hard to compare the data to the baseline of the US or a similar country that I've experienced firsthand.
second visualization: country snapshots
I really like this visualization because you have the option to compare data or look at an individual country. This data also has a lot more countries, which is nice because the user can do more exploration. While there is missing data for some countries, they report everything they can, which is cool because you can still see as much as possible. One thing I wish I could do is add a third or fourth country- the data is presented so narrowly so there is definitely room to add more columns (and maybe add a sidescroll if you add too many). It seems unnecessary to make the data so narrow if you can't see more than two at once.