This 3-page worksheet includes a short description of four experiments and asks students to identify the independent variable, dependent variable, control groups, experimental group(s) and possible hypothesis for each one. This version includes a detailed answer key and explanations, over 5 pages in total. [My other product Experiments & Identifying Variables v1.0 includes the same experiments, but no answer key and fewer questions.]

The worksheet could be used as homework, classwork, a long "Do Now," or even a short quiz. If simply read and answered, the worksheet could be completed with the class in less than 10 minutes. If students are allowed to think-pair-share or the class engages in discussion about each, the entire worksheet could take 20 minutes or more. In my own classroom, I usually work through the first two experiments with my class. I assign the third and fourth for homework and discuss them at a later date.

The experiments reflect simplified, but authentic experimental work that real-life scientists might take-on, rather than superficial "classroom" experiments. For some of the experiments, there are more than one possible correct answer, as is usually the case in real life. The reasoning behind these answers are discussed in the answer key.
For this reason, the worksheet should be used with high school students or advanced middle school students.