Reading Sections: SAT vs. ACT
Both SAT and ACT have reading sections -- and they don't get much press. They are pretty typical read-the-passage-answer-the-questions multiple choice style sections. But, there are some subtle but important differences between the sections.
First, and most importantly, there is a timing difference.
SAT: 65 minutes, 52 questions, five passages (one is actually a pair of passages) with about 10 questions for each passage/pair of passages.
ACT: 35 minutes, 40 questions, four passages with 10 questions each.
The difference here is striking: over a minute per question on SAT and under a minute per question on ACT. Moreover, timing is particularly critical on the reading section because running out of time often doesn't mean not getting to the last few questions, but rather it means not getting to the entire last set of questions. Of course some students just barely run out of time, but a lot of students run out of time in the middle of reading that last passage (or just as they finish it). On SAT, that means not answering about 1/5 of the questions. On ACT it means not answering 1/4 of the questions. That's a big difference.
So, benefits of SAT: slower pace and smaller hit it you run out of time while reading the last passage.
Benefits of ACT: less reading, less test fatigue.
Bottom line: slow readers are probably better off with SAT. Students who tire or bore easily might try ACT.
The number of passages matters too, in a few ways. More passages, obviously means more reading. But, more passages also means that each passage carries a bit less weight. So, students who might be apt to bomb out on a particular passage have less to lose on the SAT. Completely misunderstanding a passage affects 1/5 of the score rather than 1/4 on the SAT.
But, what about the double passage section on the SAT? It's true. One of the "passages" on the SAT is actually a set of two passages that contain opposing views. It's more reading than a single passage and more cognitive work to sort them out (although, in my opinion, if you can keep the passages straight in your head, the questions on the double passage set are actually a bit easier than the questions for the single passages). But, this is an area where slow readers might find the SAT unbearable. Lots of reading before you get to the questions.
However, one must also consider passage length. The passages are, on average, a bit shorter on SAT. SAT passages range from 450-850 words, with many passages right in the 650 zone. At least two of the passages also contain a chart or a graph, which is more work, but it typically means a shorter passage (3-4 questions on each SAT reading section draw from a chart or graph in one of two passages). In contrast, the ACT has no charts or graphs and the passages are between 650 and 850, with the modal passage towards the higher end. In the end, SAT takers will do a bit more reading over 5 passages, but given that the passages are a bit shorter, they will not read many more words than an ACT taker will.
Bottom line: SAT still better for most slow readers. Students who are good at graphs and charts also want to seriously consider SAT.
So, what about the content of the sections?
Both tests start with a fiction section, that is ripped right from the middle of a novel, with almost no introduction. For many students it's the hardest passage on either test. The answers feel a bit more subjective, and if you miss the hints at the context of the passage (which are there, but can be subtle) you can miss a lot of questions, even if you get the general idea of the passage that is presented.
After the fiction section, ACT presents a social science passage, which is usually economics, history, or political science. Although SAT is not explicit about it (ACT labels each passage "prose fiction," "social science," "humanities," and "natural science"), the second passage on SAT is usually also social science, which is usually economics, psychology, anthropology or sociology. On SAT this passage tends to cover a contemporary and somewhat interesting topic and tends to read more like a high-end magazine feature than a text book. ACT's social science passages tend to be a bit more staid.
Next, SAT provides the first of its two natural science passages. This first one tends to be more popular science, less technical and more accessible. This passage often contains a graph or chart. I would argue that the difficulty level of this section is about the same as the last passage in ACT, its "natural science" passage, which does not tend to get too technical.
The last section SAT provides is typically a more technical natural science passage. This passage often contains a graph or chart, and tends to "get into the weeds" in terms of the technical aspects of an experiment or theory (and the topics are obscure, like tidal patterns and genetic trends). It's a difficult reading passage. But, for the more literal minded test taker, it can actually be easier than the fiction passage. If you can follow the passage (and not get bogged down in the words or concepts that are new and unfamiliar) the answers are all there. I'd say that there is no equivalent to this passage in the ACT.
The fourth passages in each test is what ACT calls a "humanities" section, which, on both tests, tends to contain essays from fields like philosophy, political science, or gender studies. These are definitely essays and definitely more complicated and difficult than the first social science passages. ACT is more likely to go with a personal essay here. SAT often uses this section to put in the two-passage set, with one essay arguing for and one against a topic (such as women's rights).
ACT is more predictable than SAT. ACT always provides the same four categories of passages. SAT does not label passages and gives itself more flexibility. It also reserve the right to change where the charts and graphs land and which topic gets two passages. These factors will vary from test to test.
I have had students argue that the ACT passages and questions are easier. I find that those students are often the same students for whom time is an issue. To know which section is best for you -- take one of each and see how you do!