Components of a Typical Laboratory Session

Pre-lab talk

A short lecture (5 – 20 min) given by the TA at the beginning of a lab session. During the pre-lab, the TA typically:

  • Introduces the experiment
  • Demonstrates selected parts of the procedure
  • Highlights safety concerns
  • Describes write-up requirements


Students generally work alone or in small groups (2-4) to complete the lab. The atmosphere can be quite chaotic because different groups are often at different stages of the experiment at any given moment. During this period, the TA walks through the room, monitoring student progress and answering questions as they arise.

Post-lab talk

This stage is typically non-existent because student groups leave the lab at different times, immediately upon completing the experiment. Thus, it is critical to define your expectations for
the lab outcomes and write-up during the pre-lab talk.

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