Inicio Octubre Anterior
Siguiente
Actividad programada por el departamento de Física y Química
Percentages and pie
charts
The use of % and pie charts in
Natural Science. Bilingual 2nd year of ESO
A contribution to the “Proyecto de Mejora de las Matemáticas”. IES José María
Pereda. Santander
In the subject “Natural Science”, our pupils in the second year of ESO use
some mathematical concepts in English for the first time, because they have
Mathematics in the first year, but not in English.
So, the use in Science of some well-known mathematical structures has to be
supported by a few previous mathematical explanations, made in English. This
is the case of percentages and pie charts, which are the objectives of the two
presentations in Power Point that form my contribution to this project.
As in many other cases, we think that only by using these structures in a
variety of subjects, we could offer them a clearer understanding of its real
meaning.
1) The percentage has proved to be for most students one of the most
out-of-reach concepts.
They have formerly heard about and worked with percentages, but our experience
shows that they only have a vague idea about how to use them and how to
calculate them.
So, the final purpose of this presentation is to improve the use of
percentages in Science, particularly in elementary Chemistry, when we work
with the composition of matter for the first time.
In the presentation entitled “Percentages”, we allow the students of 2nd year
of ESO to revisit the idea of percentage and to use it more accurately as
possible in Science.
Look at the pdf of this presentation:
In the next one you can click into it to view the presentation step by step:
Download the
presentation
The presentation has two different parts: one specifically devoted to
mathematical concepts, and the other, with a few applications to Chemistry.
From slide 2 to 6, a mathematical introduction of percentages is offered,
based on tables, used by further explanations. The slides are animated, to use
them step-by-step, giving time for students to ask and answer questions.
Slides 7 to 9 contain some examples of percentages that appear in the syllabus
of our 2nd- year Natural Science.
a) First example (Slides 7 and 8)
At the beginning of the Chemistry course, the students have to learn the names
and symbols of some chemical elements. It is an appropriate moment to start by
using percentages.
b) Second example (Slide 9)
In the part of Biology we have firstly to study the composition of the human
body:
– The elements, and
– The compounds, with special reference to the amount of water.
It could be another good moment to use percentages.
c) Finally, in the slide 10 there are some explanations and questions about
how to transform a fraction into % in problems related to human mass. In the
11th slide, there is an introduction to the idea of pie chart.
Activity
2) A pie chart is a very clear way to express fractions and
percentages, because, at first sight, everyone can interpret the relative
proportions shown in it. So, it is one of most common statistical tools we
can use.
Look at the pdf of this presentation:
In the next one you can click into it to view the presentation step by step:
Download the
presentation
In the presentation
called “Pie charts”, slides 2 to 4 include some mathematical explanations about
the way in which fractions and percentages are connected to pie charts.
A solved example is shown in slide 5. Slides 6 and 7 explain how a % can be
transformed into a pie chart, and there is an exercise to apply what they have
learnt in the 8th slide.
Some other not-totally-developed examples of exercises in Natural Science are
provided in the rest of the slides, the most difficult being those which
transform percentages into pie charts.
Activity
Titles and credits
complete both presentations.
Mª del Carmen Urlanga Zubillaga
Departamento de Física y Química
Inicio Octubre Anterior
Siguiente