Wednesday, January 23, 2013

NGSS Have Problems

You can read a review of NGSS at  However, that's not the entire story.  Here's the rest of the story.

In the NGSS, "crosscutting concepts" are concepts that span all disciplines of science and engineering and help, according to the authors, to tie the standards together.  As a chemist, I look at those associated with chemistry standards.  I also look most closely at high school standards to see what the highest level of the standards do.

The crosscutting concepts in high school chemistry (Structure and Properties of Matter and Chemical Reactions) are listed as follows:

  • Cause and Effect
  • Systems and System Models
  • Energy and Matter
  • Structure and Function
  • Stability and Change
  • Patterns
The one crosscutting concept I see missing here is Obtaining First-Hand Data from the Real World.

Science is about exploring the real world and is an open exercise that explores what really happens, not what should happen in an ideal system.  While ideal systems are used as models against which to compare real data, scientists don't really care about models except as a tool.

Here's one sample standard that exemplifies the approach of the NGSS.

Analyze and interpret provided data about bulk properties of various substances to support claims about the relative strength of the interactions among particles in the substance.
 The standard does not specify whether the provided data are to be real or manufactured.  In this instance, you might infer that data are real.

In the section on Forces and Interactions, you'll find the following standard that is much less clear.

Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on macroscopic objects, their mass, and acceleration.
 From where do these data arise?  Is it from student experiments, from teacher experiments or demonstrations, or from a formula?  Very often, the data will come from a simulation, e.g. a formula.  You can expect teachers, when allowed by their state and local standards, to resort to this easier and more "reliable" approach whenever possible.

What does it mean to analyze manufactured data?  Here, you're using F=ma to generate data, and those data are then used to infer that the model they represent is F=ma.  This sort of thing is ludicrous.  I'd use stronger language but refrain out of respect for the reader.

This is a closed cycle.  A formula generates data that are used to verify the same formula.  In science, however, it's always an open system.  Data come from the real world, or as America's Lab Report  (ALR) says, "the material world."  Indeed, ALR insists that data originate in the material word in order for an activity truly to be a science investigation.  Ultimately, these data are analyzed and may result in a model of the real world.

The difference is as night and day.  Where ALR focuses on student actually obtaining their own data for the most part, NGSS has students working with provided data.  Is there no hope?

Later on, the following standard provides some relief.

Design and conduct an investigation to support claims about how electric and magnetic fields are created.
Here, students must do experiments and collect their own data.  However, there's one minor problem as the Clarification Statement shows.
Qualitative observations only.
So, here is the one actual piece of lab work in HS.Forces and Interactions, and it's entirely qualitative.   You cannot do much with purely qualitative data.

Finally, under Energy, you can find a real lab.

Design and conduct an investigation to support the claim that the transfer of thermal energy between components results in a more uniform energy distribution among the components of a closed system
In this standard, students are requested to "[use] mathematical thinking to describe the energy changes both quantitatively and conceptually."

That's it for the physical science portion of the standards.  One quantitative investigation and one qualitative one -- for an entire year of physical science or for two years of chemistry and physics.

To be fair, these are "core concepts," and states, districts, and teachers are free to add to them and extend them.  However, if the states and districts do not mandate laboratory investigations, then teachers will tend to avoid the extra time and budgetary stress of true lab investigations.

I find these standards to be rather shallow for leaving out important concepts (e.g. the mole) and for failing to insist on more first-hand quantitative investigations.

They've become so enamored of their cross-cutting concepts and of integrating engineering into science that they've lost the very essence of science.

© 2013 by Smart Science Education Inc., U.S.A.
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