When conducting a science experiment, how many variables should students change at a time?

In a science experiment, it is essential for students to change only one variable at a time. This is because a variable is any factor that can be changed or controlled in an experiment. By changing one variable, students can observe and measure the effects of that specific change, allowing them to draw clear and accurate conclusions about the relationship between the variable and the outcome.

If multiple variables are changed simultaneously, it becomes difficult to determine which variable is responsible for any observed effects. This can lead to confusion and incorrect conclusions. By maintaining a controlled approach of modifying only one variable, students can ensure the reliability and validity of their experimental results, fostering a better understanding of the scientific method.