Next Generation Science Standards

What do you do when NGSS gets the science wrong?

I was a scientist for about 20 years, but now work for a science education company.  I was shocked to find that NGSS contains quite few misconceptions and that led me here to ask what do teachers do when the standards get the science wrong? Probably the two most important biochemical processes on earth are photosynthesis and cell respiration, yet NGSS get these flat-out, 100% wrong. These are the statements in NGSS that are incorrect:

Cell Respiration:

NGSS DCI PS3.D "The chemical reaction of these molecules with oxygen releases energy." [by the end of grade 8]: "Both the burning of fuel and cellular digestion in plants and animals involve chemical reactions with oxygen that release stored energy."

NGSS DCI LS1.C. [by the end of grade 8]: " In most animals and plants, oxygen reacts with carbon-containing molecules (sugars) to provide energy and produce carbon dioxide."

NGSS DCI LS2.B. [by the end of grade 8]: "for example, when molecules from food react with oxygen captured from the environment, the carbon dioxide and water thus produced"

Photosynthesis:

NGSS DCI PS3. D. "By the end of grade 8. The chemical reaction by which plants produce complex food molecules (sugars) requires an energy input (i.e., from sunlight) to occur. In this reaction, carbon dioxide and water combine to form carbon-based organic molecules and release oxygen. "

How do you, as a teacher, tackle this problem – teach to the standard, or try to explain that the standard is incorrect and teach the science?

Thanks!

Tom

Tom Robertson
Tom Robertson
20 Activity Points

Hi, Tom.  

First, I strongly suggest that you post this in the NSTA biology listserv.  You'll get a lot more (and better) responses. Second, can you please explain (a) which parts of these statements are incorrect and (b) how you would suggest they should be stated differently?

Thanks,

Matt

Matt Bobrowsky
Matthew Bobrowsky
4280 Activity Points

Hi Matt,

Apologies for the tardy reply!

1. Can you tell me how to send to the NSTA biology listserv please?

2. NGSS state that oxygen and sugars react directly with each other to produce carbon dioxide and water.  This is incorrect.  Sugars are split by glycolysis and move into the mitochondria and enter the krebs cycle.  This produces electron carriers (and CO2 as a side product) that deliver electrons to the electron transport chain that then move down the chain to create a hydrogen ion (proton) gradient that drives ATP synthase.  Oxygen accepts the electrons, which forms water (with hydrogen ions).

3. Photosynthesis: NGSS states that in the presence of light enery carbon dioxide and water react with each other to produce sugars and oxygen.  Light energy is used to excite electrons that move down a transport chain to create a hydrogen ion gradient to drive ATP synthase (similar to cellular respiration). Electrons are provided to the chain by the splitting of water.  The electrons are used to make NADPH.  Carbon dioxide is fixed in the Calvin cycle that uses the ATP and NADPH to create sugars.

If we expect our students to progress to be scientists, I think the standards should get these processes correct.

Thanks,

Tom

 

 

Tom Robertson
Tom Robertson
20 Activity Points

I believe that the intent was that you share your post with the Biology forum in the Learning Center.

Also, you are referring to the middle school standards in your original post. The intent of the NGSS is to help students develop conceptual understandings. Even at the high school level, assessment of the standards on energy for life does not include the steps of the biochemical pathways involved. I do touch on these even though they are not assessed, especially when students show some interest - and explain that there is so much more that they will learn about the details of the pathways involved should they choose to pursue those interests at the university level. 

 

 

Cris DeWolf
Cris DeWolf
11345 Activity Points

I was waiting to see your post in the Life Science forum to see how these teachers responded and didn't see this post. 

The detailed pathways for both cellular respiration and photosynthesis are not spelled out specifically in the statements you provided. That is where the curricula fills in. These are standards, that is guidelines for what students should understand. While the information you provided in your second post is not in the standards, textbooks and instructional materials will include more content information. 

As middle school standards, I do not believe that students will be taught incorrect information but grade-level appropriate information. From my experience, high school instructors will go into the pathways, knowing that the content is not spelled out in the standards, but the expectation of knowing cellular respiration and photosynthesis. When they teach, the details will be provided. Middle School instructors will go in the depth appropriate for their students. 

Bev DeVore-Wedding
Bev Bev DeVore-Wedding
3425 Activity Points

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