What’s the Big Idea?

Whether you have been digesting the Next Generation Science Standards or revamping an AP curriculum, you will have noticed that modern standards focus on very broad general elements that serve as themes throughout a science curriculum, across grade levels and even across disciplines.

In AP Biology, these themes are called “Big Ideas”

Big Idea 1: Evolution -The process of evolution drives the diversity and unity of life.

Big Idea 2: Cellular Processes: Energy and Communication – biological systems utilize free energy and molecular building blocks to grow, to reproduce, and to maintain dynamic homeostasis.

Big Idea 3: Genetics and Information Transfer- Living systems store, retrieve, transmit, and respond to information essential to life processes.

Big Idea 4: Interactions – Biological systems interact, and these systems and their interactions possess complex properties.

In the NGSS, they are called “Disciplinary Core Ideas” and they are arranged in Life Science (LS) categories

students_working_smLS1A: Structure and Function
LS1B:  Growth and Development of Organisms
LS1C: Organization for Matter and Energy Flow in Organisms
LS1D:  Information Processing

LS2A:  Interdependent Relationships in Ecosystems
LS2B: Cycles of Matter and Energy Transfer in Ecosystems
LS2C:  Ecosystems Dynamics, Functioning and Resilience
LS2D:  Social Interactions and Group Behavior

LS3A: Inheritance of Traits
LS3B: Variation of Traits

LS4A:  Evidence of Common Ancestry and Diversity
LS4B: Natural Selection
LS4C:  Adaptation
LS4D:  Biodiversity and Humans

You might notice that the two are strangely parallel:

LS1A-D  =  Big Idea 2
Ls2 A-D =  Big Idea 4
LS3 A-B = Big Idea 3
LS4 A-D = Evolution

One of the hardest tasks I’ve confronted since redesigning the AP curriculum (and now aligning all classes to NGSS) is the idea of trimming content details in favor of broad ideas.  For each lesson, for each chapter, I must ask myself, where does this fit in, does it follow one of the core ideas.   For the amount of time allotted to get through all the labs in AP biology, there isn’t much time to dig into every little detail of a topic, which I think has resulted in a growing popularity of “flipped classes”, where you can send the kids home to watch a lecture  or video that covers the content knowledge and leaves the class open for discussions and labs.   The flipped class isn’t a bad idea if you have students with access and the motivation to do this type of work on their own time.  I’ve been running a hybrid flipped class with mixed results.  I estimate only 50-60% of my students are getting the content knowledge at home.

Assessments must also be reworked, as the typical multiple choice test focuses more on details, and less on big ideas and broad topic understanding.  This isn’t to say that multiple choice tests are impossible, but you would have to be sure that each question is valid with respect to the DCI or AP Big Ideas.   To that end, many of my tests in AP Biology have been converted to a mix of multiple choice and short and long form answers, similar to the AP Test they take in the spring.

Before starting a unit of study, it may be helpful for to look at the CORE IDEAS and develop a list of essential questions that will be addressed in the unit.   Consider these your unit goals, which can be broken down into smaller objectives later.

Essential Question Checklist

1.  Does the question center around a student relevant major issue, problem, concern, or interest?
2.  Does the question encourage collaboration or discussion?
3.   Does the question have more than one right answer?
4.  Does the question ask the learner to plan a course of action or make a decision?
5.  Does the question invite exploration of ideas?
6.  Does the question of meaning within the context of science?  Does it probe for deeper understanding?
7.  Is the question open-ended?  Will it result in further questioning?

In AP Biology, the first section deals with the nature of science and scientific practices.  My essential questions for that chapter are:

Science is a body of knowledge, how is that knowledge gathered?  (Think about historic science and modern science.)
How would you design an experiment?
What is the role of a Theory in Science?
What is the relationship between science and technology?
How are living things classified and why is it necessary to develop an organization scheme?
How does evolution explain the diversity of life?

 I think my assessments now are more authentic, but students seem to actually prefer the old format to tests, where they could get a good grade if they would just memorize facts about the topic.    After returning the tests, I had students complain the test questions weren’t in the notes, or that they weren’t sure what to study.   I think it’s a valid observation, as open ended questions have built in uncertainty.    My hope is that students will become more comfortable with this format as the class progresses and that I will get better at being more transparent with expectations.