Nature of Science & Engineering
The Practice of Science

Science is a way of knowing about the natural world and is characterized by empirical criteria, logical argument and skeptical review.

Benchmark: Bias in Investigations

Understand that prior expectations can create bias when conducting scientific investigations.

For example: Students often continue to think that air is not matter, even though they have contrary evidence from investigations.

Benchmark: Analysis of Reliability

Understand that when similar investigations give different results, the challenge is to judge whether the differences are significant, and if further studies are required. 

For example: Use mean and range to analyze the reliability of experimental results.


Standard in Lay Terms 

Science is a way of knowing the world around us that is different from other disciplines.  It uses measurements and facts to build knowledge.

Big Ideas and Essential Understandings 

Big Idea:

Science uses observations and evidence to create lines of reasoning to explain the natural world and how things work. It is a way of thinking and looking at the world. Students, in science class need to look at the world through "scientific eyes". Students often come to class with misconceptions. The science classroom address these issues by engaging students in investigations, data analysis and careful consideration of results.  Students see that bias created by misunderstanding can influence investigations. Scientific reasoning and process leads students to distinguishing the difference between data that is reliable and data that is not reliable.

Benchmark Cluster 

MN Standard Benchmarks

Understand that prior expectations can create bias when conducting scientific investigations.

For example: Students often continue to think that air is not matter, even though they have contrary evidence from investigations.

Understand that when similar investigations give different results, the challenge is to judge whether the differences are significant, and if further studies are required.

For example: Use mean and range to analyze the reliability of experimental results.



©Gary Larson


History and Nature of Science

Content Standard G
As a result of activities in grade 7, all students should develop understanding of


1.    Science as a human endeavor

2.    Nature of science

3.    History of science

Seventh Grade

At this level, students need to become more systematic and sophisticated in conducting their investigations, some of which may last for weeks or more. That means closing in on an understanding of what constitutes a good experiment. The concept of controlling variables is straightforward but achieving it in practice is difficult. Students can make some headway, however, by participating in enough experimental investigations (not to the exclusion, of course, of other kinds of investigations) and explicitly discussing how explanation relates to experimental design.


Student investigations ought to constitute a significant part-but only a part-of the total science experience. Systematic learning of science concepts must also have a place in the curriculum, for it is not possible for students to discover all the concepts they need to learn, or to observe all of the phenomena they need to encounter, solely through their own laboratory investigations. And even though the main purpose of student investigations is to help students learn how science works, it is important to back up such experience with selected readings. This level is a good time to introduce stories (true and fictional) of scientists making discoveries-not just world-famous scientists, but scientists of very different backgrounds, ages, cultures, places, and times.


By the end of the 8th grade, students should know that

  • Scientists differ greatly in what phenomena they study and how they go about their work. 1B/M1a
  • Scientific investigations usually involve the collection of relevant data, the use of logical reasoning, and the application of imagination in devising hypotheses and explanations to make sense of the collected data. 1B/M1b*
  • If more than one variable changes at the same time in an experiment, the outcome of the experiment may not be clearly attributable to any one variable. It may not always be possible to prevent outside variables from influencing an investigation (or even to identify all of the variables). 1B/M2ab
  • Collaboration among investigators can often lead to research designs that are able to deal with situations where it is not possible to control all of the variables. 1B/M2c*
  • What people expect to observe often affects what they actually do observe. Strong beliefs about what should happen in particular circumstances can prevent them from detecting other results. 1B/M3ab
  • Scientists know about the danger of prior expectations to objectivity and take steps to try and avoid it when designing investigations and examining data. One safeguard is to have different investigators conduct independent studies of the same questions. 1B/M3cd

Common Core Standards

If using animals to collect data could cross over with social studies in biome areas.

English standards by writing research papers.

Math connections with range and mean, graphs, Excel spreadsheets for organizing data


Student Misconceptions 
  • Students will be able to explain how their prior expectations can create bias when conducting their experimental research project.
  • students tend to invoke personal experiences as evidence to justify a particular hypothesis. They seem to think of evidence as selected from what is already known or from personal experience or second-hand sources, not as information produced by experiment. [1]
  • Most 6th-graders can judge whether evidence is related to a theory, although they do not always evaluate this evidence correctly. [2]
  • When asked to use evidence to judge a theory, students of all ages may make only theory-based responses with no reference made to the presented evidence. Sometimes this appears to be because the available evidence conflicts with the students' beliefs. [3]

[1] Roseberry, A., Warren, B., Conant, F. (1992). Appropriating scientific discourse: Findings from language minority classrooms. Journal of the Learning Sciences, 2, 61-94.

[2] Kuhn, D., Amsel, E., O'Loughlin, M., Beilin, H. (1988). The development of scientific thinking skills. Academic Press.

[3] Kuhn, D., Amsel, E., O'Loughlin, M. (1988).The development of scientific thinking skills. Academic Press.

  • Students tend to look for or accept evidence that is consistent with their prior beliefs and either distort or fail to generate evidence that is inconsistent with these beliefs. These deficiencies tend to mitigate over time and with experience. [1]

[1] Schauble, L. (1990). Belief revision in children: The role of prior knowledge and strategies for generating evidence. Journal of Experimental Child Psychology, 49, 31-57.


The following classroom setting could take place at the beginning of a unit dealing     with how science works. It specifically has students seeing how observations can be interpreted in a unique manner.

Mr. Q stands at the front of the classroom and flips off the light. "What just happened?" he asks. "You turned out the light. You cut the power. The lights aren't getting electricity, so they don't work", were some of the responses. He pulls out a flashlight, clicks the button and points it around the room. Grabbing a match, striking it against the cover, Mr. Q lights a candle. "Dark suckers, suck dark. These are just a few of the dark suckers we use on a daily basis, without giving them a second thought. This is a primitive dark sucker.

Notice the color of the wick, when I extinguish the dark sucker."

Mason says, "It is black."

"Why is that?" probes Mr. Q.

"It is black because it is burned!" replies Danita.

"No, it is black because of the dark it has sucked in." counters Mr. Q.

The students are starting to get a little agitated, as Mr. Q continues his dialogue.

"The wick was white to begin and now it is black because it has pulled in dark. If I hold a pencil next to the operating dark sucker, what happens to the pencil?"

Sue answers, "It will turn black."


"Because of soot, I think." Sue replied, engaged in the observation and explanation.

"Nope, because it got in the way of the dark getting sucked into the wick."

A collective groan comes over the room and now students are furiously raising their hands trying to bring out point after point to disprove Mr. Q.

"Power plants produce electricity that travels in wires! The lights give off light that is why we have shadows! Light bulbs don't quit working because they are full of dark, they just wear out! The switch is not a valve that controls the flow of dark to the power plants, and they don't release it over and over again!" Oh, the blood is roiling the room and the students are standing. Challenging every point that Mr. Q makes.

Calmly he addresses every question and points out how the dark works. "That's right, dark has mass. You've all been swimming in the lake. Go deep and what is the status of the dark....lots of it. Dark has mass and so it sinks."

"NO, NO, NO!" come the pitched voices of the crowd.

Mr. Q finally pulls the students back to manageable din. He addresses the students and gets them to the point of the activity. He provided them with observations, that he  interpreted. His interpretations, however crazy, were just that.

Was the wick black? Did the dark go away when he flipped the switch? Do light bulbs stop working?

The observations can lead to questions. Questions can lead to investigations and new data. New inferences are made as the data is collected, analyzed and discussed. Science is a way of learning about how things work based on collecting good information, logical reasoning, and keeping an open mind.


Instructional Notes 

Instructional suggestions/options:

  • Dark Suckers or lots of other sites, just Google this topic. Students come with lots of history about light that you can take advantage of with this discrepant event.
  • DHMO This is another idea that can point to why students need to be scientifically literate. A quick lesson idea is to have student read a summary sheet about DHMO and then create a poster about the topic for public information. That is one class period, then the next day you talk about what DHMO actually is....and perhaps sing a song about it.
  • Skeleton People This tongue in cheek article is great for looking at observations (skeletons) and the inferences surrounding them (they were a race of skinless people).

Selected activities:

  • - Measuring Shadows To determine the pattern (length and direction) of shadows cast by sunlight during a several month period and to develop an interpretation of the daily and seasonal patterns and variations observed. For the most part, change should not be taught as a separate topic. At every opportunity throughout the school year, the theme of change should be brought up in the context of the science, mathematics, or technology being studied. In the earliest grades, children should be encouraged to observe change and describe it. Once they have a variety of experiences with change, they are ready to start thinking more abstractly about patterns of change.
  • - Mathematics and Environmental Concerns The activities in these lessons focus on connections between mathematics and environmental concerns. Students participate in activities in which they investigate the data in connection with recyclable materials and develop plans to help the environment. They are designed to make students aware of various materials that people ordinarily use and discard, to increase their knowledge of the numbers of material that people use, and to make plans to use materials more conservatively. Plans may include reducing material used, reusing materials, or recycling them. Each activity includes gathering, graphing, and interpreting data, thus extending opportunities for communicating, reasoning, and problem solving. Each activity features ideas to share with classmates or family members. Most students want to make a difference in saving the earth, and these activities can help them get a start or extend their efforts in this appealing and important area.
  • Showing students that CO2 has a greater density than air by using baking soda and vinegar to put out a candle. This simple demonstration could be used in the first portion of any 7th grade science course that introduces some inquiry.
  • Using the imploding can. With a hot plate, heat an empty pop can with a bit of water in it. When the water hits a boil, carefully invert it into some water. Start with observations, then move to hypotheses and on into testing. This simple lab could be used in the first portion of any 7th grade science course that introduces some inquiry.
  • Cartesian Divers. You need a glass bottle with concave and convex side (plastic 2-liter pop bottles work also).  That is part of the discrepant event. Using a bulb pipette, get it to barely float in water and place it into the bottle (which is full to top of water). Screw the lid on and then let the fun begin. Use a battery, by rubbing the side of bottle to make the dropper sink. Then move to sound vibrations or have students sing and the pipette sink. All the while, students are making observations, posing hypotheses, creating tests....

       Cartesian Diver from the Exploratorium Museum.

  • - Brine Shrimp  1 and 2 : Hatching Brine Shrimp To develop an understanding of how the growth and survival of an organism (brine shrimp) depends on physical conditions. This is accomplished by designing an experiment to determine the optimum salinity of water needed to hatch brine shrimp. This lesson is the first of a two-part series on brine shrimp. These lessons relate to the idea in the central benchmark that in any particular environment, the growth and survival of organisms depend on the physical conditions.  To determine the reliability of data students may be asked to  count the surviving brine  shrimp from each of the different salinities and apply a statistical anlaysis of their counts, such as mean and range.      (
New Vocabulary 


  • fact - In science, an observation that has been repeatedly confirmed.
  • hypothesis - A testable statement about the natural world that can be used to build more complex inferences and explanations.
  • scientific law - A descriptive generalization about how some aspect of the  natural world behaves under stated circumstances.
  • scientific theory -  In science, a well-substantiated explanation of some aspect of the natural world that can incorporate fact, laws, inferences, and tested hypotheses.
  • peer review: Critique of one's writings/work by others with common interest
  • empirical criteria-verified by observaion or experience        
  • science The use of evidence to construct testable explanations and predictions of natural phenomena, as well as the knowledge generated through this process.

(National Academy of Sciences, Institute of Medicine. (2008). Science evolution and creationism. Washington D.C.: National Academies Press.)

Technology Connections 

Internet connections if possible for students. If you can get internet connections in your lab it is much easier for students to do their work.

Cameras/flip videos/microscopes  all can be interfaced with computers to store images to be transferred for  use in power point presentations, or to store images for use with other sections. Collect and store data for observational or experimental studies.

Web-based Journey North

Journey North is a free, internet-based program that explores the interrelated aspects of seasonal change. Through interrelated investigations, students discover that sunlight drives all living systems and they learn about the dynamic ecosystem that surrounds and connects them. 

Hardware cameras that connect to microscopes- used in labs, observational studies. If you have cameras that fit onto a microscope, a whole new world comes alive to students.

Smartboard technology for teachers

Cross Curricular Connections 

Graphs, mean and range, need to be covered before this is taught.



Formative Assessment:

How will you judge a source of information? Given some of the activities listed above, how do you perform skeptical review?

How does bias and previous perception/ideas influence interpretation of data or experimental design?

An objective assessment where students are presented with data and an erroneous interpretation of the data based on personal bias and ask students to create a strategy to correct the interpretation and explain how the personal bias influenced the interpretation.

Summative Assessment

In an experiment's conclusion, how have students included how their bias may have influenced their data analysis and interpretation.

How have scientific data and their interpretation been influenced by public opinion in the past? What are some current issues that are influenced by public input and opinions?

Teachers: Questions could be used as self-reflection or in professional development sessions.

Are students biases caused by prior teaching methods of earlier grade levels? How might these biases be addressed?

Have you conferred with math teachers regarding their insights into teaching students graphing skills?

Could models be used to help determine bias? In what way?


Students collecting data and determining if there is a bias

See the vignette above and look at how basic observations can lead to misleading conclusions. Students need to have lots of opportunities to look at real time data from current issues that occur daily, weekly. An administrator should see students analyzing events in real time, and see students studying science and society in that interface.


Struggling Learners 

Struggling and At-Risk:

It is misguided to focus on the mastery of basic skills before asking students to achieve higher-order skills.  Instruction in basic skills must be seen as part of the larger task of learning to think well. 

Instruction in basic skills must be done in concert with the larger task of learning higher-order skills.

English Language Learners 

There is a tendency to place ELL students in low ability classes rather than consider their actual abilities.

ELL students learn most proficiently when they are taught English across the curriculum.  It is especially productive to integrate science and English teaching.  Hands-on science learning promotes language connections

Students must be encouraged to write as much as possible, both in their home language and in English.  It is difficult to move to higher and higher levels of abstraction without the support of language connections.

The same type of teaching and learning experiences do not work equally effectively for all cultural groups. 

Extending the Learning 


Accelerating the instruction of able students promotes their intellectual development.  It is not harmful and does not harm their social or emotional development.

Areas of concern in gifted education include the labeling of gifted learners, culturally diverse gifted learners, disabled gifted learners, gifted females, and career education for the gifted.  

Gifted students need many opportunities and time for reflection to make sense of their experiences to fully master scientific inquiry. 


Science education should include the use of culturally relevant content.  (Ferguson, Robert. "If Multicultural Science Education Standards' Existed, What Would They Look Like?."Journal of Science Teacher Education. 19.6 (2008): 547-564. Print.) The above author have proposed several ways to integrate culturally relevant content into the curriculum.  The value of using such approaches is that they can improve the conversation about beliefs in science and hone beliefs about science for all students.

Students should be given opportunities to do science rather than read about it.  Doing science includes reasoning about science.  This kind of science emphasizes the active role of the learner in constructing knowledge. 

Science instruction should not be isolated from the rest of the students' lives.  The contextualization of tasks can make a difference in performance.  Many science experiences are those of a special world, confusing, often couterintuitive and counter to daily experiences.  When students can participate in and observe science in the ordinary world in which they live, they are more likely to learn as well as come to appreciate science as a way of knowing.  When this can be embedded in a cultural context the possibilities for new understanding and connections become even stronger. 

Special Education 
  • Accurate classification of children is difficult and classification systems used to place children in special programs is problematic.
  • Learning experiences should be as multi-sensory as possible and safe.  Such experiences have an added benefit too.  They are effective with all learners. 
  • Instruction should include direct experience with the materials of science.