Teaching in labs

Labs provide students with hands-on experience and the opportunity to explore methods used by experts in their discipline. Those teaching a lab will need to know their department’s and/or supervising instructor’s expectations; develop clear instructions; and be prepared to ask questions to stimulate students’ thinking. In addition, it is the lab teacher’s responsibility to ensure that safety standards are followed.

Below you will find further information to help in teaching a lab section.

Preparing to conduct a lab

Your department might require you to attend weekly lab trainings or provide other ways for you to prepare for a specific lab. Make sure that you have enough information so that you would be able to conduct the experiment on your own. Here are the things you will need to do to prepare:

• Identify and attend any lab trainings or preparation sessions required by your department.
• Brush up on the topics and meet with your supervisor to clarify procedures. Consider how you will demonstrate new or difficult practices.
• Determine what materials and equipment are needed. Find out from your lab coordinator, lab tech, and/or supervising instructor if there is anything you need to acquire on your own.
• Identify potential problems. Make time to run an unfamiliar experiment yourself first, so that you can identify shortcomings in the lab procedure, equipment, and materials.
• Determine how much time the experiment will take. Expect students to take longer than you.
• Review the lab manual. Identify any passages in the lab manual that might be confusing. Consult with your department and/or supervising instructor about any needed updates.
• Anticipate student questions. Draft answers to questions students are likely to ask and consider preparing a brief list of pointers to present at the start of the lab.
• Understand safety hazards and procedures. You are responsible for knowing the relevant safety procedures and what to do if there is a safety-related incident. Consult with your department and/or supervising instructor about required safety training or readings you need to complete (e.g., UW’s safety resources for teaching labs). Don’t be afraid to ask questions if any safety issues have not been explained well enough for you.
• Reflect on past labs you have supervised or observed—what went well and what could be improved?
• Determine whether students will be required to complete any pre-lab work. If you are a teaching assistant, be sure to consult with your supervising instructor to determine whether you are responsible for confirming whether students have completed required training and how to handle students who have not.
• Understand clean-up procedures and expectations. Find out how you will be expected to clean your workspace after the lab in accordance with municipal, state, and federal guidelines. How much time will you need to allow for cleaning? What role will students play in cleaning the lab? Talk with your supervising instructor and any other relevant course staff about the best ways to encourage and enforce student clean-up duties throughout the lab sessions.

At the beginning of the lab

• Model safe lab practices and wear appropriate attire and safety gear.
• Provide a brief overview of the lab (2–5 min), including its purpose and how it relates to recent concepts covered in class/homework (especially any pre-lab assignment) or to current issues in the discipline. Point out the key concepts or themes students should reflect on during the lab.
• Explain safety hazards and procedures to students.
• Explain cleaning procedures students will be expected to perform.
• Clarify any potential ambiguities in the lab manual and share any pointers you developed in advance.
• Demonstrate special procedures at the beginning of class rather than interrupt the experiment later.
• Explain what you will be looking for when you grade their lab work. Share any rubrics or grading criteria with students. If you are a teaching assistant, ask your supervising instructor for a rubric or grading criteria.
• Invite questions from students.

During the lab

• Try to talk with each student/group at least once during the experiment. Safety, technical, and procedural matters can be handled quickly in a few words of advice.
• Ask questions to help students practice the steps of scientific inquiry. Push beyond simple yes/no questions or confirmation questions like “You’ve got this, right?,” which lead students to answer quickly and affirmatively before really thinking. Consider asking questions such as: What question does this part of the lab investigate? What is your hypothesis? What data do you need to collect to test this hypothesis and why? What data have you collected? What conclusions do the data support?
• Help students troubleshoot their own conceptual challenges. If a student asks, “Why can’t we get this to come out right?”, try asking a series of questions to lead them to discover answers on their own. Although it is tempting to help students by saying, “I see where you went wrong,” your students will learn more if you challenge them to figure out the answers on their own.
• Be professional and model intellectual humility. Students will expect you to be an authority, but this does not mean you have to know everything. If you don’t know the answer to a question, let students know and promise to get back to them later.
• If many students are struggling with the same question or step, ask the class to pause their work so you can provide guidance to all students.
• Restate students’ clean-up responsibilities and give them sufficient time to complete them.
• Collect assignments and remind students about any post-lab work due dates.