My advice is simply to get better at reading. That may sound obvious but if you are able to read at a high speed and understand what you're reading without spacing out, you will easily finish the reading section with confidence in your answers that is vital for heading into the science section. There are no tricks and no need to skim as the test was made for decently fast readers to finish before the time.
The best way to do this is to read challenging material and to read it frequently. Reading harry potter will not help your score at all. If I were you I would pick up a copy of the new york times(not a local newspaper!) and read one article a day for a few months. This will increase your score TREMENDOUSLY.
The logic behind this is all but one of your ACT passages are non-fiction. Reading newspaper articles will train you to focus on things you have no interest in. The small text of newspapers also increases your reading level. And look at the size of the ACT passages. They are identical to the size of newspaper articles.
Hope that helped. However, if you are a senior and looking to get a last test in before applying this method won't be of much use. Remember, the skills gained from this method are important to both college success and life after college! So read, read, read!
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