Always save the conflicting viewpoints passage for last. You can easily figure out which one this is, because there will be references to scientists 1 and 2 or students 1 and 2 or something along those lines. This passage will take the most time to complete, because you must thoroughly read it before you can answer the questions. Do not risk running out of time for the easier questions by starting this passage before finishing the rest of the Science Test. Remember that time is your greatest resource on the ACT. Use it wisely!