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This is a collection of classroom lessons to help high school biology teachers more effectively teach basic concepts in the areas of evolution and the nature of science. They were developed and tested during nine years of summer institutes by biology teachers from across the nation.

SITE INTEGRITY is maintained through the oversight by the three co-directors of ENSI:
Dr. Jean Beard (Biology Ed.)
Dr. Craig E. Nelson (Biology)
Dr. Martin Nickels (Anthropology)
and continuous feedback from the many ENSI and SENSI teachers, professors and other users of this site. Check the People section for photos and bios of these people.

NSF Logo

We are especially grateful to theNational Science Foundation for funding these institutes over the years and for extending that funding to the development and maintenance of this web site (NSF/TPE: 88-555-60 and 90-555-85 to Indiana University, and 91-552-59 to San Jose State University). We are also grateful to Indiana University for allowing us the use of their web server to make this material freely available to teachers.


3 December 2014

NSTA-Sponsored Podcast:
About the Science Surprises e-text for students
Using ENSI Nature of Science Lessons

Also... New Bio-Science Resource Site Added:

20 October 2014

Exceptional Online Resources
for Teaching Evolution and NOS
Selected Summaries and Links from the
Life Discovery Conference 2014

HHMI BioInteractive:
            Anoles Evolution Virtual Lab
            The Beak of the Finch
Avida-Ed Digital Evolution Software: Evolution in the Classroom
BoxCar2D: Evolving Better Cars:
            Teaching Evolution by Natural Selection
            Design Competition
Climate Change: Teaching This Through the Life Sciences: Resources
Modeling and the NGSS
Science Forward Video Series: NOS and other videos available online

ALSO: Timely Information from Understanding Evolution (Oct. 2014):
Ebola and Evolution
Two Highest-Rated Lessons (grades 6-16):
- Artificially Seleccting Dogs (from UCM)P
- Making of the Fittest: Natural Selection & Adaptation (from HHMI)

23 August 2014
Human Evolution
Special Issue of the latest
Scientific American
September 2014

Our Skulls Lab hasn't been updated for about 15 years.
If you do that lab, you can share lots of stuff from this issue
of Scientific American, showing what a dynamic and changing subject
Paleoanthropology is. Human evolution is still one of the best examples
of the science of evolution, with many coming from
fossil studies,
DNA analyses,
primate studies.
Talk about the power of multiple lines of evidence!
If you develop any new materials for teaching
human evolution,
please share with us.

14 July 2014

New Evolution Survey Quiz
As of 14 July 2014, we have a new improved version of the Evolution Survey. This will replace the earlier version (posted since 2010). The new 2014 version has items roughly grouped by category; many have been reworded to be less ambiguous; all are adjusted to 7th grade reading level (or lower). There are similar numbers of true and false statements, somewhat randomly arranged so that not too many of the same answers are together. Thanks goes to ENSI user Laura Tulijak for the preliminary work on this.

24 May 2014

Active Learning: How to Do It (NEW 5/14):
All of the lessons on the ENSI site involve (and expect) active learning (or interactive learning) that is student-centered. This involves frequent use of “Think-Pair-Share” strategies and other tools. If you are not familiar with how to do this, or would like some help to implement or improve interactive learning in your classroom, then this collection of “Active Learning” tutorials (video clips) is a “must” for you.

11 May 2014

Perspectives & Resources
by Douglas Allchin
REVIEW: In this new book, Allchin makes the excellent case for using authentic science historical narratives to teach what the real processes of science involve. Eveyone loves a good story! In addition to providing the rational for this, and several excellent examples, Allchin offers a rich collection of tips for developing your own narratives. 2013.

12 May 2014

New Text Supplement for Teaching
Nature of Science
Reflecting the ENSI Approach

Science Surprises: Exploring the Nature of Science is available again as an e-book Click Here for details.

17 February 2014

New Evo-Devo Book Review
Another book by Lewis Held, Jr.
How the Snake Lost its Legs
Fascinating Evo-Devo discoveries of the many
Tantalizing Traits in the Animal Kingdom

CLICK HERE for Review

20 January 2014

Another busy year for the 16th year of ENSIWEB
Take a Look at What We've Accomplished,
and What's Ahead.

12 January 2014

The NEW Science Surprises

Science literacy is a vaccine against the charlatans of the world that would exploit your ignorance.
Neil deGrasse Tyson

Have you noticed a certain lack of science literacy in many (most?) of our legislators (and many other people)? Have you also noticed a significant lack of critical thinking skills in your students? And are you aware of the many misconceptions people have about science?  At the same time, have you also noticed that virtually all science textbooks deal poorly (incompletely and/or inaccurately) with many important aspects of the nature of science (NOS), including critical thinking skills?

WE HAVE A SOLUTION! A text supplement is now available for use with any science textbook. It can supplement the first chapter of your text, or completely replace it. It’s called Science Surprises. In fact, this is actually an introductory UNIT on the nature of science, suitable for any secondary science class. It includes the Science Surprises student text, the Teacher’s Guide, and several of the excellent, classroom-tested NOS lessons freely accessible from the ENSI website. CLICK HERE FOR DETAILS.

8 January 2014

Our Whale Evolution Lesson: Becoming Whales
has several new figures and resources added.
(Go to "Materials" and click to get pictures.)
There are now two choices for the set of six fossil whales
(both updated and sharp).
There are two new diagrams
showing how India was “rafted” north
and rammed into Asia,
even a side view animation
showing how the continental plates came together,
the Tethys Sea bottom scraped off
and scrunched up to become the Himalayas.
With sound effects!
Check them out.
Also, an improved page with 6 modern whales.
And a link to YouTube video clips from the
PBS Darwin’s Dangerous Idea series, part 2
("Great Transformations")
showing studies of whale evolution
(see link in Teacher’s Materials).
Improved version of Darwin’s Evolutionary Tree.
All bad links have been corrected or removed.
Finally, an intriguing whale cartoon –
good for discussion.

14 October 2013

Evolution: Education & Outreach
Article Access

Evolution: Education & Outreach journal is now open access
(=free access), thanks to Springer Link Publishers.

These are excellent and useful articles by professional scientists about the many aspects of evolutionary science and the teaching of those topics, for secondary and university teachers. Each issue includes an editorial, curriculum / education articles, several original scientific articles, and media reviews. CLICK HERE for easy access to volumes/issues for any of several topics.

4 August 2013

Many of the ENSI lessons already address the
NGSS, CCS, and STEM Expectations.
We have listed those lessons here:
Index to Lessons Meeting NGSS, CCS, STEM
STEM Applications of Natural Selection 
Scientific Argumentation (NGSS, CCS) 

9 July 2013
New Lesson that focuses on
Scientific Argumentation
a Key Objective for the NGSS.
Includes links to latest issue of NSTA's
The Science Teacher with several articles
on Scientific Argumentation.
Original Checks Lab lesson also modified
to stress Scientific Argumentation as well

24 June 2013

NEW EXTENSION: Molecular Aspects of Origami Bird.
This study not only brings a genetic/DNA connection to the
natural selection of origami birds,
but it brings a more accurate understanding of
certain important elements of natural selection. (June 2012).

23 June 2013

How to Win the Evolution War: Teach Macroevolution
By Kevin Padian
"If the American public understood what is actually known about the major evolutionary transitions in the history of life and how we know about them, uncertainty about evolution would drop precipitously, creationist arguments would fall on deaf ears, and public education in biology would make much more sense than it now does. Macroevolution must take a much more prominent place in K-12 science teaching. To do so, a curriculum must be redeveloped at both K-12 and college levels, so that preparation in macroevolution is a required part of K-12 biology preparation" [emphasis added]. Evolution: Education and Outreach, v.3, issue 2, June 2010.
Commentary about meeting NGSS standards,
with links to resources are added.

23 June 2013


A recent study (2013) shows that if teachers know the likely misconceptions that their students have about a topic, those students will show greater gains than if the teacher just knows the accurate science involved. This makes a very strong case for assessing students to see what misconceptions they may have about each upcoming general topic. Our Science Knowledge Survey measures common misconceptions about the nature of science, and our Evolution Survey does likewise for evolution.

2 June 2013

Two Items for Nature of Science Experiences
from 3-D Molecular Design.

Here are two novel sets of materials to add to your collection of NOS teaching tools. One is called The Data Dilemma – Modeling Scientific Practice. The other is called The Mystery Tubes – A Black Box Activity. They both come with presentation procedures and discussion questions. They also have lists of the national NGSS that they satisfy. They are available from 3-D Molecular Design.

21 February 2013
Join the World of Genomics Studies
Learn a Valuable Skill.

Do you have students interested in the applications of their DNA knowledge? How about students looking for independent projects for science fair or extra credit? Or how about having your lab assistants learn to use the materials of genomics studies? Any computer whizzes in your classes? Working with these materials could be a snap for them.

Click here for more details

 27 January 2013
NEW: Artificial Selection Lab
Kindly Contributed to ENSIweb by
Dr. Theodore Garland, Jr. and
Dr. Tricia Radojcic
BORN to RUN: Artificial Selection Lab

Students are introduced to the field of experimental evolution by evaluating skeletal changes in mice that have been artificially selected over many generations for the behavioral trait of voluntary exercise wheel running. A video presentation by Dr. Theodore Garland, Jr. of the University of California, Riverside discusses the experimental design and presents the results of the collaborative research on the structural, metabolic, and neural changes in the selected lines of mice. In an inquiry-based activity, students develop hypotheses about the skeletal changes that might occur in the legs of the selected mouse populations and design an investigation using measurements taken from photographed femurs (thigh bones) of mice from both selected lines and non-selected control lines.

 19 January 2013


ENSI Annual Report for 2012
for Compelling Connection between
Microevolution and Macroevolution

Hominid Chromosomes Article:
Look for the February edition of the NABT journal,
The American Biology Teacher.  In that issue, you will find an article on
Chromosome Connections: Compelling Clues to Common Ancestry” by ENSIweb Webmaster Larry Flammer.  Here’s the abstract of that article:

Students compare banding patterns on hominid chromosomes, and see striking evidence of their common ancestry.  To test this, the human #2 chromosome is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome #2 resulted from the fusion of the two shorter chromosomes.  Students test that hypothesis by looking for (and finding) DNA evidence of telomere segments at the fusion site, reinforcing the likelihood of our common ancestry with chimps, and showing us that we all carry the “molecular fossils” of telomere fusion!  Students see how multiple lines of evidence make a compelling case for common ancestry, and they experience an important element of inquiry: testing hypotheses.

28 November 2012

Alternative article to Women’s Brains: Confirmation Bias by Physicist Chris Lee (Go to Women’s Brains, scroll down to Extensions & Variations, then to Confirmation Bias in Science).

Here is an interesting (and perhaps easier-to-read) article describing two examples of confirmation bias. The article was written by a practicing scientist who points out the value of double-blind studies where judgment is involved in the results (as is common in many pseudoscience topics, where double-blind tests are not used, or used poorly).  Discussion questions provided.

He also shares one of his own experiences with a new scientific idea, develops a theoretical model, and tests the model (tries to destroy the model). He then shares what happened when he presented the idea to his peers at a conference. In this context, the author points a key difference between science deniers and scientists.

Investigative Study (New Lesson): Therapeutic Touch: An Inquiry
Students perform a single-blind study that tests the “placebo effect” in friends and family. The placebo effect is a form of confirmation bias. Class discussions follow.

27 October 2012

Go to “What IS the Nature of Science?” page
to find these added pages:
NOS Ten Key Concepts
NOS Elements & Benefits
Science Assumptions & Limits
NOS-ENSI Lesson-Selection Matrix

STEM lessons already on the ENSI site
Science IS – is NOT new Summary Worksheet

These additions have come mostly from the field-testing of a forthcoming booklet for students on the nature of science: Science Surprises.  The Science IS – is NOT worksheet was developed by middle school teacher Christine Evans.  It was done to transfer the results of this lesson (in Sunsets, Souls and Senses) to a convenient Summary sheet for future reference.

The STEM lessons are those already on the ENSI site that satisfy some of the STEM expectations.

Finally, for teachers unsure about the need for taking 2-3 weeks to teach the nature of science explicitly, take a look at the number of Misconceptions by Teachers for Teaching the Nature and Processes of Science, by the Understanding Science team.

23 August 2012

The Growing Need for Solid Introduction to
Evolution and Medicine
in High School Biology

1. We see an increasing need (and clear benefit) for the understanding of evolution in medical training.
2. However, medical schools and pre-med programs are already crammed, little room for adding extensive evolution content.
3. Medicine is becoming an increasingly useful application for evolution, with a growing number of examples that you could use.  Pre-college teachers should try to incorporate such examples into the biology/life science courses.
4. Using medicine as a major application of biology in general, and evolution in particular, can help to fill this educational gap.
5. Doing this fits closely with the growing focus on the use of STEMM (STEM+ Medicine) in pre-college science courses.
6. It turns out that medical applications of evolution provide an engaging and relevant approach to introducing and teaching evolution in high school biology, and even middle school life science
7. For several excellent, tested, useful (and free) materials for bringing real evolution applications in medicine into your biological science classes, click here.

25 July 2012

A Few New Additions – LINKS to…

New Site by Nate Fairchild:
with Effective Approach
Using ENSI and other Lessons for
(scroll down to 7th Grade Life Science)


New Lesson on
on the
Understanding Evolution Site.
Includes Phylogeny and DNA Work
(scroll down to Extensions and Variations #7)

Perceptions Not Always Reality lesson
(scroll down to end of page: Other Resources)
Or See it at
BrainDen Optical Illusions

2 July 2012
An Engaging New Lesson on
Natural Selection
on the Neuron website.

New HHMI Holiday Lecture DVDs:
The Origin of Modern Humans
October 2011

Our Popular
With Three Lessons is Back.
Lessons A & B are good to go.
Lesson C still needs some work, but...
A & B alone are still effective in
demonstrating strong DNA evidence
for Common Ancestry

24 March 2012
For the INVESTIGATING EVOLUTION QUESTIONS (Tutorial) lesson, we have added updated versions of the Student Instructions to this excellent intro to using online genomic databases and tools.

New PowerPoint added: ONE-GENE-ONE-ENZYME animation,
using the GULO Pseudogene as an example

To WOMEN'S BRAINS lesson (on S. J. Gould's essay on bias)
we have added a link to commentary on Gould's own bias in his essay
The Mismeasure of Man (interesting irony)

3 worksheets on chromosomes and speciation
by ENSI contributor Tom Mueller:
Chromosome Shuffle,
Human-Chimp DNA, and
Strange Case of Oliver the Chimpanzee

for ongoing discussion on this subject with
Tom, Craig Nelson, and ENSI teachers
with an added link to Definitions & Explanations

In our QUICK SPECIATION activity, added this as an
example of Allopatry

4 January 2012


Click Here for Annual Report

27 November 2011
Evolution: Education & Outreach Journal
Offering Free Access to its Articles in 15 Issues
Until 2012

This journal, with its many excellent articles on evolution and the teaching of evolution, is kindly allowing
FREE downloads
of any of the articles¬Ý (as PDF files) in their 15 issues,
from now until December 31, 2011.
Click Here for Details.

 23 October 2011

AIDS: Using Evolution
to Solve a Medical Problem

Chimp to Man: The Path of AIDS
Opening paragraph: "Our story begins sometime close to 1921, somewhere between the Sanaga River in Cameroon and the Congo River in the former Belgian Congo. It involves chimps and monkeys, hunters and butchers, “free women” and prostitutes, syringes and plasma-sellers, evil colonial lawmakers and decent colonial doctors with the best of intentions. And a virus that, against all odds, appears to have made it from one ape in the central African jungle to one Haitian bureaucrat leaving Zaire for home and then to a few dozen men in California gay bars before it was even noticed ,Äî about 60 years after its journey began." Click Here to get complete article and teaching tips.

20 September 2011


1. Richard Dawkins Profile article in NY Times, Science Section, Sept. 20. Interesting and informative. Search NY Times online for article: “A Knack for Bashing Orthodoxy.”

2. Jane Goodall live broadcast to a theater near you, Sept. 27. See www.FathomEvents.com/jane for list of theaters nationwide, and tickets.

3. Bio-Survey Opportunity for Harvard Study. Contact Jaimie Miller jmiller@cfa.harvard.edu before early October. Based on misconceptions, for middle school, high school teachers and classes.

4. HHMI’s “Bones, Stones, and Genes: The Origin of Modern Humans” watch live Oct. 6 & 7. Go to the HHMI site at http://www.hhmi.org/biointeractive/ to register and see schedule.

5. AIBS/NESCent Evolution Symposium and Teaching Workshop at the NABT conference in Anaheim, CA, October 14-15. See http://www.aibs.org/events/special-symposia/changing_humans.html for details.

6. Bring Evolution to Your School/Community for Darwin Day 2012. Apply to be a stop on NESCent’s 2012 Darwin Day Roadshow. See http://roadshow.nescent.org/ for details and registration (by October 31). Or email Jory Weintraub at jory@nescent.org

 13 May 2011
ANNOUNCEMENTS (Click Here for Details)

Evolution Education Opportunities This Summer

New Assessment Tool for Misconceptions from AAAS

New Laetoli Trackway Files Avalible as HD PDF files

Do-It-Yourself DNA Kit files revised

PowerPoint for Whale Evolution lessons

 1 April 2011
Our ANNUAL REPORT for 2010 - FINALLY completed? Get an overview of the ENSIweb changes over the past year - and check out our HIT counter -

MAGIC HOOEY STICK: New commercial source for multiple Hooey Sticks, along with teaching strategy and other teacher information must be obtained with teacher request to webmaster using school email address.

FOOTSTEPS DATA: There have been teacher requests for published estimates (by professional paleoanthropologists) of the actual footlengths and stature (height) of the people who made the Laetoli tracks. Those data are now listed (from two sources), linked-to from the Footsteps in Time lesson, and include some suggested projects and other actions for students to explore further. The companion lesson, Lengthy Relationships, has also been extensively improved (mostly in its PDF handout).

FOSSIL PATTERNS in TIME: This article was published in the February 2011 issue of Science Scope (NSTA journal for middle school teachers). The article (by ENSI webmaster Larry Flammer) presents an overview of the Patterns in Time lesson on the ENSI site.

 20 March 2011


Thanks to teacher suggestion, we now have a digital version of the Laetoli Topo trackway. Many teachers over the past several years have used the full scale enlargement of this trackway to give their students the exciting opportunity to walk in the 3.6 million-year-old footsteps of "Lucy" (Australopithicus afarensis) - and make a number of discoveries by analyzing those tracks (see our Footsteps in Time and the Laetoli Trackway Puzzle lessons). Now, you can just download the very sharp 300 dpi trackway and have it printed out directly in full scale (5X enlargement) at any print shop. Click on title above to see how to get the NEW DIGITAL TRACKWAY.

Laetoli Trackway: a Teaching Tool
in South Africa
Dr. Terry Hutter in the CESLA outreach project.

Dr. Hutter works in Subsaharan Africa, largely through the CESLA project that he helped establish, to bring hands-on education to a wide range of people over much of South Africa, living especially in rural areas. He has used the Laetoli Topo Trackway as part of his African Origins presentations, to groups from elementary through secondary, tertiary and adult groups, to rural indigenous poor groups throughout South Africa, and to private schools there. Dr. Hutter has kindly sent us some of the pictures he's taken of students using the trackway. Some of them are posted here, which you could use as PPT slides in your presentations.Click on title to see pictures.

 8 February 2011

New Pre-Test Tool
to Measure
Understanding of Natural Selection
Effective Strategy
to Teach
Understanding of Natural Selection
1. Conceptual Inventory of Natural Selection - the "CINS" test
- a 20-item tool analyzed for reliability to measure accurate
understanding about natural selection
2. Modeling Natural Selection - Using model-based inquiry
and wikis to learn about evolution
Still Another Effective Strategy
for Repairing NS Misconceptions
A Review/Summary and links from
ENSI Co-Director, Craig E. Nelson

7 January 2011 
WELCOME TO 2011 and the 14th year of ENSIweb

Recent Advances and Research in Molecular Evolution
from the NESCent/AIBS Evolution Symposium at the
November 2010 NABT Conference in Minneapolis
Videos of illustrated talks from
four leading researchers are now available.
Get a better understanding of "genotype-phenotype" relationships;
Explore a number of common misconceptions
about evolutionary concepts;
Free teaching resources, activities, papers and short videos.
See Details

Also, see the excellent article on
"Dinosaurs' Living Descendents" in the
December 2010 issue of the Smithsonian magazine.
Recent discoveries, mostly of feathered dinosaurs in China,
have virtually clinched the dinosaur ancestry connection to today's birds.
See Smithsonian.com site for the article
with excellent illustrations,
including an interactive version
of the Bird/Dinosaur Family Tree shown in the article.

 26 September 2010
Additions in Classification and Tree-Thinking

1. Sample Unit for Classification and Diversity of Life,
with materials ready to use

2. Added to Phylogenies & Tree-Thinking:
a. David Baums's evolutionary tree QUIZ for pre-post testing
b. Baum's excellent figures for teaching Tree-Thinking - in PowerPoint
c, Access to Peabody Museum materials on Tree-Thinking
d. Access to articles in NSTA and NABT journals - for members
e. Using "cartoon" figures to expose misconceptions
about family trees and evolution

 17 September 2010


Using RING SPECIES Demonstration
for Compelling Connection between
Microevolution and Macroevolution

How Do Chromosome Changes Survive
to Produce New Species?

 9 September 2010
Nonsense on Stilts -
How to Tell Science from Bunk

by Biologist/Philosopher/Skeptic Massimo Pigliucci

Quirks of Human Anatomy -
An Evo-Devo Look at the Human Body

by Molecular Biologist Lewis Held

New hump-backed dinosaur
with evidence for earlier origin of feathers

Directions for making and using the "Phantom Tube" illusion
Great for teaching the realm and process of science
Population Genetics:
Hardy-Weinberg interactive
Quick Speciation Lab
PopGen Fishbowl online interactive

 17 August 2010
We have a variety of upgrades; Most Notably:
New INQUIRY segment for analyzing pattern
New Pre/Post Quiz
New Accumulation of Traits diagram

Revised Handout
All keys and explanation removed...
(so unavailable to students)
contact webmaster on school email for info

 19 March 2010

Your Inner Fish - PowerPoint Slides
Update for Ensatina Studies (Step in Speciation)
Short Videos Explaining Evolution
Human Evolution Mosaic - Interactive
Ten Myths About Darwin
Pseudoscience Resources
Comments on Evolution Articles in ABT Feb. 2010

 16 February 2010
Major Revision of

with easier-to-use "TimeScaleMarkers,"
Student Handout with Info & Directions,
Key to Chronology of Fossil Vertebrates
Updated PDF of the Entire Lesson -
(with Standards met in this lesson)

 4 February 2010
Don't Miss this month's issue of
The American Biology Teacher
Devoted entirely to articles on Teaching Evolution
Click here for list of articles and commentary

ALSO - Don't Miss "Creation"
the Book and Film about Darwin's Life

The film is currently playing in more theaters
check local listings
See Review and Teaching Suggestions

 22 January 2010
Primate Cladogram, Based on Chromosome Banding Patterns
used in Nuts & Bolts, and Chromosome Comparisons PPT

Darwin's Tree (from his Origin of Species)
typos corrected, groups labeled
used in Nuts & Bolts, and other lessons

Site Map Updated

12 February 2010

 3 January 2010
A brief overview of ENSI's beginnings...
its transition to ENSIWEB...
and ENSIWEB's track record.

NEW ADDITION to Patterns In Time:
See the Overview PowerPoint for Teachers,
along with ideas for its use in the lesson itself

 All the lessons on this web site are copyrighted by ENSI, or posted with permission of its source.
This material may be copied only for noncommercial classroom teaching purposes, and only if this source is clearly cited.

Number of Visits Since October 1998: