Understanding variables
This complete PowerPoint lesson for KS3 science includes a range of differentiated and stretch and challenge activities.
The PowerPoint includes teaching notes and lesson activities designed to increase participation in the lesson, as well as clear learning objectives. By the end of the lesson, all students will be able to define independent, dependent and control variables and identify these variables in scientific investigations.
There are three carefully scaffolded group tasks. Students initially define the different types of variables.
They then consider the variables in an example investigation: Does the mass of magnesium added to acid affect how much hydrogen gas is produced?
In groups, students will each look at a different example investigation, before sharing their findings with another group. There are six in total, including a series circuit, a photosynthesis investigation and a temperature change investigation.
The lesson also includes two extension tasks for fast finishers or higher attaining students.
The accompanying Word document is for groups to record their answers and ideas from their discussion.
Definitions of the three types of variables from the KS3 science resource:
- The independent variable is the variable that is altered during an experiment.
-
The dependent variable is the variable being tested and measured.
-
Control variables are the variables that must be kept the same throughout the experiment.
