Appropriate statistical test for a student lab?
To choose the right statistical method (it is more than just saying "use the t-test") you need to think about your experiment. A good starting point is this figure from Bitesizebio:



There are two relevant articles on that website:


Let’s Talk About Stats: Comparing Two Sets of Data
Let’s Talk About Stats: Comparing Multiple Datasets


Probably also interesting is the definition of statistical terms:


Let’s Talk About Stats: Understanding the Lingo