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FORENSIC SCIENCE
highest standards or which have
made the most significant improvements in science, we found
Scientific enquiry (Sc1) at the heart
of science work. Teachers in these
schools describe not only the
increased levels of motivation but
also the ways in which Sc1 has
promoted learning in the
programmes of study for Life
processes and living things, Materials
and their properties and Physical
processes. In the best schools this
belief in the significance of Sc1 to
learning is underpinned by clear
inclusion of Sc1 in schemes of
work, in such a way that
progression in Sc1 is set out,
through planning of science activities, effective sharing of good
practice and systematic monitoring of teaching and learning.
It is exhilarating to see young
people working hard and enjoying
what they are doing. Her Majesty’s
Inspectorate (HMI) have access to
the large amount of evidence
gathered through school inspections by Ofsted teams, and
this is augmented by visits of HMI
to schools. This considerable
wealth of data allows us to
identify the issues that are
impacting on the quality of
science education. This work is
directed at further improvements
in the standards of science
education our children receive. I
would offer four areas for
improvement in primary science
education:
Making the most of scientific
enquiry.
Making better use of
assessment for learning.
Improving the coordination/
leadership of science.
Improving teachers’
knowledge and understanding
of science.
Ian Richardson HMI is the
Specialist Adviser for Science
with Her Majesty’s
Inspectorate. E-mail:
[email protected]
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PRIMARY SCIENCE REVIEW 90 • Nov/Dec 2005
IVOR HICKEY,
COLETTE MURPHY,
JIM BEGGS AND
KAREN CARLISLE
DESCRIBE HOW
PRIMARY SCHOOL
CHILDREN CAN CARRY
OUT
DNA
FINGERPRINTING
L
ooking at the assembled
10- and 11-year-old children in front of me, I
became increasingly convinced that this had been a very bad
idea indeed. However, I would need
to get the lesson started. I tentatively
asked, ‘Does anyone know what the
branch of police work that deals with
DNA analysis is called?’ Possibly, I
thought, one or two of the brightest
might be able to attempt an answer.
The room erupted into a forest
of waving arms and faces that
appeared to be crying out ‘Ask me,
please!’ Every child in the class knew
the answer – forensics – and I
realised immediately that I was on
to a winner. It was quite clear that
the children not only knew about
DNA but they were really interested
in it and its role in crime detection.
They described numerous television
series from CSI to The Bill in which
DNA extracted from the scene of the
crime was used to track down and
identify suspects. The level of
motivation was higher than I had
experienced for any topic I had ever
dealt with in a school.
My roller-coaster morning was the
final phase of a project we had
developed with funding from
Science Year in conjunction with a
number of Belfast primary schools
FORENSIC SCIENCE
Figure 1 Children get a
close-up view of DNA
samples for fingerprinting
being loaded into gel
in which we introduced the process
of DNA fingerprinting as part of a
wider programme to investigate
children’s attitudes to science.
Children’s understanding
of complex ideas
There are two main difficulties in
taking DNA fingerprinting into the
primary school in any meaningful
manner. The first is how to explain
what is taking place to the children
in a way they will understand, and
the second is the problem of
equipment. We were able to supply
the necessary equipment from our
laboratories in college, and devised
a scheme in which BEd studentteachers who specialised in science
worked in the schools, in conjunction with their tutors. The
trainees explained the processes
involved and carried out the
Only one will match the pattern
produced by the DNA found at the
‘scene of crime’.
These procedures are obviously
too complex for primary-age
children to understand. Our
problem was to translate the
science into a form that was
understandable by the children,
while still being scientifically
accurate. Explanation of enzymes
and their ability to digest a specific
in the classroom
practical demonstration of DNA
fingerprinting, using knowledge
they had acquired during their
science modules.
Importantly, however, it was the
children who interpreted the data
and applied their findings to
solving the crime. DNA fingerprinting can be carried out in a
number of ways. We based our
approach on a DNA fingerprinting
kit produced for schools by Bio-Rad,
a well known supplier of molecular
biological materials to researchers
(see website). The kit contains five
samples of DNA, one representing
DNA extracted from biological
material found at the scene of a
hypothetical ‘crime’ and four taken
from ‘suspects’. The DNA is digested
by restriction enzymes and each of
the suspects’ samples produces a
unique pattern of fragments when
separated by gel electrophoresis.
sequence of bases in DNA was
clearly out of the question. In
discussion with our students, we
decided to omit the concept of
enzyme digestion and simply state
that DNA from different people
breaks up into fragments of
different lengths when being
analysed. This was because children understand that DNA differs
from person to person, since we
differ in eye colour and other
inherited traits. The children
followed this explanation with ease
as they already had a general idea
that genes are what make us
different form each other.
We felt that we would have
difficulties finding a meaningful
explanation of the process of
electrophoresis – where the
fragments of DNA are separated by
forcing them through a gel by
means of an electric current. We
were surprised to find that from
their understanding of the topic of
electricity at key stage 2, children
were able to grasp the concept of
fragments of DNA moving through
a gel in an electric current, and that
the smaller fragments move more
quickly than large ones.
Preparing the ground
In our opinion, science teaching is
more successful when embedded
with other areas of the curriculum,
such as literacy. We asked class
teachers to prepare the ground for
DNA fingerprinting by getting
children to develop their own
‘murder scenarios’. The children set
about this with great gusto: some
classes wrote stories, others
developed dramas with children
acting the parts of victims and
suspects. When the scene had been
set in this way, each school was
visited by a team of three or four
students who briefly outlined the
process of DNA fingerprinting.
They then carried out a practical
demonstration in which the
children were able to watch the
DNA samples being loaded into an
electrophoresis gel, and the
apparatus being attached to a
power supply. After 45 minutes the
power was switched off, and the
gels removed.
Analysing the DNA
evidence from ‘suspects’
The children could then see how
dye from the samples had moved
into the gel. The DNA remained
PRIMARY SCIENCE REVIEW 90 • Nov/Dec 2005 7
FORENSIC SCIENCE
invisible at this stage and required
overnight staining; by next morning
the staining was completed and the
results were unveiled. Fortunately
our students had performed
excellently and in each case the
‘right’ results were obtained!
Children were then allowed to
examine the gels for themselves.
They compared the patterns
produced by DNA found at the scene
of the crime with those produced by
DNA from each of the suspects;
nearly all the children picked the
correct one. This allowed the
scenarios to be completed; the guilty
party was known, and the next step
was to develop motives. Children set
about this with considerable
enthusiasm: some of the motives
were spine chilling to say the least.
One school even went so far as to
set up a court scene with judge, jury
and defending and prosecuting
barristers.
Being on the inside of
science
The responses of the children show
that the programme was most
definitely a big hit. Why should this
be the case? Given that the science
content was derived from more
advanced syllabuses, it might be
thought that the children would
have found it rather esoteric and
dull. The reason for success appears
to be that all the children had
knowledge of DNA, developed not
from their school curriculum but
from television dramas and in some
cases news programmes. This
allowed them to identify with the
process and to enjoy playing the
role of detectives. In addition,
although the children had learned
what DNA fingerprinting can be
used for, they had never seen the
laboratory processes involved. In a
very real sense, our children enjoyed
‘being on the inside of science’ and
making the decisions from real data
where they had seen the experiment
carried out. Including a literacy
aspect to the programme only
increased their enjoyment by
allowing them to link real science
data to their imaginary crime
scenarios.
This type of practical experience
helps children to develop their
interest in science. The key is not
content or process skills, but the
experience
of
amazement,
enjoyment and inspiration, as
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PRIMARY SCIENCE REVIEW 90 • Nov/Dec 2005
demonstrated in the intense
concentration of the girl in Figure
1 watching the DNA sample being
loaded. In our college training
modules for intending primary
teachers, practical classes on DNA
extraction are always included.
These are based on extraction from
onions, kiwi or other plant material,
using protocols widely available on
the Web (see website). The point is
to enable children (and often the
students too) to experience the
‘wow!’ factor of seeing DNA appear
in a test-tube before their very eyes,
as a result of their personal
manipulation skills.
Given the children’s pre-existing
interest in DNA fingerprinting, we
were surprised to note that in a
survey of primary schools in
Northern Ireland only a small
majority of teachers used the terms
DNA or genes even with year 7 (11/
12 year-olds) classes (Hickey and
Quinn, 2002). Admittedly, these
terms are not found in the
programme of studies, but with the
interest in the topic displayed by
children it might be valuable to
include this sort of topic to
stimulate children’s perception of
science. DNA is linked to variation
in human populations and hence
also has a relevance to citizenship
education. At a time when there is
clear evidence that children are
losing their interest in science
education (Murphy and Beggs,
2003) it is vitally important that we
take advantage of the areas of
science that children experience in
the world outside school, to fire
their imagination and encourage
them to take the subject further.
How can you do it?
Finally, there is the obvious
question: ‘How could I run this sort
of programme with my class?’ Clearly,
even well-funded primary schools
are unlikely to be able to afford the
apparatus necessary for this type of
activity, and not all primary teachers
will have the time or inclination to
develop the necessary manipulative
skills. However, this need not
prevent upper primary classes from
having this sort of scientific
experience. We used college
equipment and students to deliver
the bulk of the programme with the
class teachers. This co-teaching
approach is very successful and
both students and teachers benefit
(Murphy et al., 2004). Many
university biology departments are
keen to make connections with
schools and often have schemes to
allow students to obtain experience
in classroom situations. And, like
us, you may be able to link with a
science/discovery centre (in our
case, W5 – see website) to stage
‘forensic days’ in which children
carry out a full investigation of a
hypothetical murder. Here again,
undergraduate students proved
excellent facilitators; contact your
local or partner science teacher
educators. Funding for such events
can be sought from a number of
sources such as the Royal Society,
and the BBSRC. So why not
introduce your class to solving a
murder using modern methods?
They will find it much more fun
than playing Cluedo!
References
Hickey, I. and Quinn, C. (2002)
Progression of scientific
terminology in education. In
Proceedings of ATSE Conference,
Science within and beyond the
National Standards. pp. 22–23.
Murphy, C. and Beggs, J. (2003)
Children’s perceptions of school
science. School Science Review,
84(308), 109–116.
Murphy, C., Beggs, J., Greenwood, J.
and Carlisle, K. (2004) Students as
‘catalysts’ in the classroom: the
impact of co-teaching between
science student teachers and
primary classroom teachers on
children’s enjoyment and learning
of science. International Journal of
Science Education, 26(8), 1023–1025.
Websites
DNA fingerprinting kit for schools
produced by Bio-Rad: http://biorad.com
Protocols for extraction of DNA:
http://gslc.genetics.utah.edu/units/
activities/extraction?
W5 (WhoWhatWhereWhenWhy):
http://www.w5online.co.uk/
Ivor Hickey and Jim Beggs are
principal lecturer and head of
science respectively at
St Mary’s University College,
Belfast. Colette Murphy is head
of learning and teaching at the
Graduate School of Education,
Queen’s University, Belfast;
Karen Carlisle is her research
associate. Email:
[email protected]