Mini Labs
(To hear me talk about mini labs, click on this podcast at Science Teaching Tips.)
Seems like all science teachers say that they want to do more labs. So why don't they? Probably becuase they seem like so much work for so little learning. They take forever to set up, for students to do, and to grade. And then at the end of all that effort, seems like the students didn't even learn anything. Regular labs, often called formal labs, do take a lot of time and students do get lost in the paperwork.
But there's an alternative... A mini-lab.
What's a Mini Lab?
A Mini Lab is a single concept activity. They are not just scaled down formal labs.
They are maximally
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highly focused. They concentrate on exactly one topic, usually in the form of a question or prediction. For example, what do you think will happen to an in focus image as the screen is moved away from the lens?
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infallible. Students shouldn't be able to do the lab wrong. All they have to do is move the lens and look at the screen. Labs where the students have to take sensitive data that you have to check to see if they are getting it right make lousy mini-labs.
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self-evident. Ooo. In the above example, the image gets spread out. No way to miss it. Or when one lab cart hits another lab cart of an equal mass, the first lab cart stops and the second seems to be moving at an equal speed.
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short. The activity should take no more than a few minutes.
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memorable. Surprising is even better, but even confirming expectations if presented correctly can catch students' attentions.
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sequenced. A single mini lab may not teach very much, but since they are short, they can be combined together to teach a more complicated topic.
Mini Labs minimize
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multiple steps. Labs that have students do a bunch of different things lose them as they get confuised about where to focus. Also, if students get unexpected answers, it may not be obvious to you where they went wrong. Try to break up a complicated lab into many smaller steps.
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formal components. Don't have them write the procedure -- with luck they did what you told them to do -- or rewrite the materials list. Do have them write down their predictions, their results, and what they think they were supposed to learn.
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bookkeeping. If they need to take lots of pieces of data and coordinate to see what is going on, go ahead and use a formal lab. On the other hand, many labs that seem complicated can be greatly simplified by breaking the lab up into parts. For example, a momentum lab that includes several different masses and velocities and conditions could be broken up into separate mini labs with each lab being just one case.
They do not replace all formal labs. They replace some formal labs, some lectures, and most demonstrations.
Mini Labs can be sequenced to teach a topic.
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Break the topic into the sequence of ideas and skills. Do just one idea at a time. For example, first investigate loudness and amplitude. Then, investigate pitch. Then, investigate how these might combine.
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Convert the ideas into a predictions. A good prediction might be, "How do you think that the motion of a speaker cone will change if you make the sound louder?" or "How do you think the motion of the speaker cone will change if you make sound higher?"
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Use their natural desire to show what they mean to teach a skill. For example, in the above example, the students will want a way to show that the speaker cone moves in and out a greater distance when the sound gets louder. They will struggle to represent this idea, and you might suggest that a graph would help them to show it.
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Make students explicitly write their new models. The question can be very simple like "What do you think that you were supposed to get out of this lab?" to something more complicated like "What do you think the speaker cone is doing to the air?, but they must write them down. It is painful and slow, but they will remember the activity forever if they do it.
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Build in reinforcing activities like homework. Give homework questions that explicitly use the model. Consider putting homework at the bottom of the mini lab handouts, if you use them.
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Try to use the same materials for multiple mini labs. It will save you effort and time setting the labs up, but more importantly, the students' familiarity with the equipment will make the labs go faster. For example, I have ten mini labs that use very nearly the same optics set up.
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Create more mini labs on a topic then you might need. It is hard to figure out how many steps you'll need for most everyone to get what's going on. Pick and chose for the class.
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Emphasize the importance of the mini lab. Don't tell the students what they were supposed to get out of the lab. On tests, require students to support their assertions by referring to a lab activity as evidence.
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Consider starting with the most surprising result. A logical and clear sequence can be boring and hard for students to get excited about. Start with something that they are unlikely to expect; often that will catch their attention and make then excited to keep investigating. For instance, my first collision is an elastic collision of carts with equal mass. One stopping and the other starting to go at nearly the same speed boggles their minds.
I didn’t invent mini labs but I really like them, obviously. Other pages here will show you what I do with them, but here are some other pages to look at.