Implementing District Standards
While I designed this unit for my third-grade students, the truth is that understanding microbes is not anywhere in the Connecticut Science Standards for elementary grades – yet it is a topic that does have an impact on their daily lives. After all, there is a reason we aske them to wash their hands! While elementary students may not be required to know about microbes, that information is essential to building a successful water filter.
The nature of his unit, however, involves using scientific knowledge to engineer a solution, and this ties directly into the eight science and engineering practices laid out in the Next Generation Science Standards. Those eight practices are:
Asking Questions and Defining Problems
In this unit, the problem is unhealthy water, and the question is “how can we make it safer to drink?”
Developing and Using Models
A practice of both science and engineering is to use and construct models as helpful tools for representing ideas and explanations. In this unit, students will construct a physical model of a working (hopefully) water filter.
Planning and Carrying Out Investigations
Scientists and engineers plan and carry out investigations in the field or laboratory, working collaboratively as well as individually. In this unit, students will use what they have learned about microbes and water treatment to investigate how they can create a water filter.
Analyzing and Interpreting Data
Scientific investigations produce data that must be analyzed in order to derive meaning. In this unit, students will collect data in the form of a count of bacterial colonies. This data will be used to judge the effectiveness of a water filter.
Using Mathematics and Computational Thinking
In both science and engineering, mathematics and computation are fundamental tools for representing physical variables and their relationships. They are used for a range of tasks such as constructing simulations; statistically analyzing data; and recognizing, expressing, and applying quantitative relationships.
Constructing Explanations and Designing Solutions
The products of science are explanations and the products of engineering are solutions. In this unit, the product is a working water filter.
Engaging in Argument from Evidence
Argumentation is the process by which explanations and solutions are reached. In this unit, students will argue whether a water source is “safe” to drink based on collected evidence.
Obtaining, Evaluating, and Communicating Information
Scientists and engineers must be able to communicate clearly and persuasively the ideas and methods they generate. Critiquing and communicating ideas individually and in groups is a critical professional activity. In this unit, students will be able to analyze the effectiveness of their filter as well as the filters of others. They can also use this information to communicate safe drinking water practices to the public.