I’ve been working with my grade 6 class on the design of science experiments. The goal is that they can state a research question, choose appropriate independent/dependent variables, and outline a procedure. This is a challenging task for students of this developmental level — in Piagetian terms, they are sliding into the formal operational stage. Designing an experiment like this is heavy on abstract thought, so plenty of scaffolding is needed.
Today, I had the students do a straightforward lab: loading mass onto a spring and measuring the length of the spring. By the end of the class, each student was able to articulate something like, “adding more mass makes the spring stretch more.”
However, the underlying goal is to get the students to work with independent and dependent variables directly, and to record their data onto a neat table. This experiment, as well as the water absorbency of soil lab we’ll do on Friday, will provide fodder for discussion next week.
A couple days ago I posted about my grade 6 class developing a model for scientific investigations, which we subsequently used as a template for our lab notebooks. Now that we have that under control (more or less!) we can start to focus on the process of designing an experiment.
I have opted to focus on four factors that guide experiment design:
1. The independent variable
2. The dependent variable
3. The controlled variables
4. A hypothesis
However, since the students have not done experiments in which they test multiple values for a variable, this is bit of a bootstrapping process. I opted to give the students written descriptions of simple experiments, asking them to identify 1-4 for each. However, despite my best efforts to engage them in the task, many did not even attempt to read for comprehension. I will need to follow up on this with our ESL support group.
There was discussion on the AMTA listserv earlier this month about lab notebooks. I think the consensus was positive. For my 6th-grade science class, there are several benefits:
- The lab notebook provides a structured way to approach and document experiments.
- The lab notebook allows for written self-expression, without getting away from a model-centered course of study.
- The lab notebook stays in the classroom, which will (hopefully, but I’m realistic) mean that it will never be ‘at home’ when we need it.
- The lab notebook serves as a cumulative, living document of our work together.
- The lab notebook documents a large number of the things I need to assess for the IB Middle Years Programme.
Of course, the first step is to create a model for how we write in our lab notebooks! Over the past week, the students have been developing models of the scientific method. I took my favourite, had the students add/delete a couple things, and then we used that to create a template for the lab notebook.
I’m especially happy about the “idea” and “safety” sections. These are not things I would have included, myself, but I think they’re great additions. The “idea” section provides a connection to familiar phenomena (or a modeling-standard introductory demonstration), while the “safety” section forces the students to think ahead to safety issues.
Today we used Scotch tape to see some static electricity in action. During the ~15 minutes between my first demonstration and the first student saying “static electricity” I was on a cloud: it was tremendous to see the students trying to grapple with something completely alien. The tape was attracted to most things, but not other tape. And especially to metal. And it was attracted to water?! And if you watched closely, a stream of water from the tap actually moved because of the tape?!!!
I didn’t have to prod or prompt anything. Children are fantastic.