In communicating observations made the information may become 'corrupted' as the other person receives the information in his frame of reference e.g. Consider an individual reporting on a 2m. dwarf pommecythere (Golden Apple) tree in full fruit -

• Observation: it as a very short tree.

This information to one unaccustomed to these dwarf plants might be perceived as a tree around 5 m high as he/she is accustomed to the larger version of the tree (typically 10 - 20 m. tall), when in fact the tree is only about 2 m. tall and extremely tall for that variety! Use of a standardized scale of measurement will result in better communication of scientific information.

All physical quantities which are measured can be either fundamental units or derived units. The fundamental units of measurement are:

Derived units are combinations of the fundamental units. We have developed instruments to measure quantities. However, please note that the basic senses are still used to acquire the 'readings'. All instruments have errors and errors may be minimized by calibration.

In communicating observations made the information may become 'corrupted' as the other person receives the information in his frame of reference e.g. Consider an individual reporting on a 2m. dwarf pommecythere (Golden Apple) tree in full fruit:

This information to one unaccustomed to these dwarf plants might be perceived as a tree around 5 m high as he/she is accustomed to the larger version of the tree (typically 10 - 20 m. tall), when in fact the tree is only about 2 m. tall and extremely tall for that variety!

Use of this standardized scale of measurement will result in better communication of scientific information.

Always record the data you obtain! The skills and consequent learning are in explaining why your data is different from the expected It is unscientific to 'ratch' or 'cook' the data to suit the expected result.

Would you like a doctor to 'ratch' your X-ray?

Or an engineer to 'ratch' the results from faulty machinery?

We naturally try to explain our world. This leads to a level of comfort in our day to day lives. People often make conclusions based on feelings and emotions. This is not science. The nature of science is explaining the data obtained through observation and measurement of space time relationships using critical thinking and scientific principles. Explanations or conclusions based on scientific principles and critical thinking are less likely to be prejudicial.

The trick is to use critical thinking and scientific principles in our explanations of observable events. Making inferences is about using our previous experiences to explain observations and measurements of space time relationships. In science we have to try and balance our creativity with critical thinking.

Inferences do not necessarily have to be correct - but they must be based on observations and measurements.

E.g. Observations - After a weekend away I observe my backyard garden of 2 week old tomato plants have wilted and some almost look dead. The days are hot and the ground is dry. The neighbour does not have healthy plants.

Conversation: Me - "I din water meh plants so dey wilt."

First Friend - "I feel the plants wilted because the neighbour jealous yuh and she have 'bad eye' so she gie the plant and dem 'maljo'. Yuh no 'najar'".

Second Friend - "Wat stupidness yuh taking? It eh have nuting like maljo. The plants belong to God and he has decided to take dem, so doh question it!"

hy? - The first is a reasonable explanation based on observable evidence but whiles the second and third may be reasonable, they are not based on observable and repeatable evidence.

We naturally try to forecast the future of our world. This leads to a level of comfort in our day to day lives as we feel better prepared to face the future. People make forecasts based on feelings and emotions. This is not science. The nature of science is predicting the data to be obtained through observation and measurement of past space time relationships using critical thinking and scientific principles.

The trick is use critical thinking and scientific principles in our forecast of observable events. Making predictions is about using our previous experiences to decide on possible outcomes of observations and measurements of space time relationships. In science we have to try and balance our creativity with critical thinking.

Predictions do not necessarily have to be correct - but they must be based on observations and measurements.

E.g. Observation - Before a weekend away I observe my backyard garden of 2 week old tomato plants are healthy. It is the dry season with hot, dry days and the ground is dry. The neighbour does not have healthy plants.

Conversation: Me - "If meh plants and dem eh water for this weekend the go wilt an ded."

First Friend - "Yuh dotish eh! I feel the plants go wilt fuh sure, because yuh neighbour jealous yuh and she have 'bad eye' so she gie the plant and dem 'maljo'. Yuh no 'najar'". Boy d plants dem ded ahready!

Second Friend - "Wat stupidness yuh taking? The plants belong to God and if he want to take dem, he go take dem in he own time so doh question it!"

Why? - The first is a reasonable forecast based on observable evidence but whiles the second and third may be reasonable, they are not based on observable and repeatable evidence.

We naturally try to generalize events in our world. This leads to a level of comfort in our day to day lives as we feel better prepared to face the future. People make forecasts based on feelings and emotions. This is not science. The nature of science is making hypotheses through observation and measurement of past space time relationships using critical thinking and scientific principles.

It is important to use critical thinking and scientific principles in making hypotheses. Consider my experience with a particular brand of soap. If I have determined that soap assists water to wash and I generalize this to all brands of soap, I am making a hypothesis.

Hypotheses do not necessarily have to be correct - but they must be based on observations and measurements linking only two variables in a measurable way.

Do you recognize that without generalizations we would have to evaluate every new situation in detail even though we have experienced similar events in the past?

E.g. I have found that in growing tomatoes during the dry season, if I water them every day I get more fruit. I make an inference "Tomato plants watered daily in the dry season produce more fruit". When I generalize this to "All plants watered daily in the dry season produce more fruit", I am making a hypothesis.

Why? - My inference is about a specific observation that I have done. My hypothesis is generalizing this observation to other similar phenomena.

Does my statement satisfy the characteristics of a hypothesis? - Yes.

We only investigate the relationship between two variables at a time, so all other variables which can affect the results of an investigation must be held constant while we try to determine the relationship between these two selected variables.

IWe identify all the quantities which can change. These are often:

The quantity we can change (manipulated variable) is changed according to our design and the change which results in the other quantity (responding variable) is recorded. All other variables are held constant during the investigation.

E.g. In determining the period of a simple pendulum the following quantities can change:

We can only investigate one of these at a time so if we want to investigate the relationship between the length of the string and the period of the pendulum all the other variables must not change so we must use the same string, bob and angle of release etc..

Experimenting is the skill to plan, design, carry out an investigation and evaluate the results of the investigation. Experimenting involves:

Science is based on observable, repeatable data. The ability to plan, design, carry out an investigation and evaluate the results is an important preparation for life skills. An understanding of how scientists conduct investigations is very important to understanding what science is.

Raw data must be presented in some organized fashion for it to be meaningful. E.g. Data on the growth of seedlings is collected in some tables. Until some kind of organization is done on the table, the data is not very meaningful. Presentation of the data in a graph will probably enhance understanding of the trends.

We try as far as possible in communication skills to develop tables or other data recording structures. In investigations the decision to take readings involves determining:

When data is collected it has to be organized to determine trends. Some of these are the use of:

E.g. if the length of the string is varied and the corresponding periods obtained for the simple pendulum the following had to be decided:

We can only accommodate the new information if it is meaningful and understandable to us. We must, therefore, make every effort to present our findings in the simplest ways.

True understanding of a concept can often be demonstrated by ones ability to explain it in simple everyday language. Results of investigations presented in complex language or only mathematical terms may not be the best for learners. As the aim of science is to make explanations for the data gathered, it is important that we find meaning in the simplest possible language.

Science is based on observable, repeatable data. The ability to test our hypotheses and to verify the results of other investigators is an important facet of the science investigative process. In addition, problem solving is not an advanced process that is reserved solely for mature learners. Indeed, people of all ages can and must be solvers of problems. Perhaps young children are the most natural problem solvers. Because they continually face circumstances that are novel, they must adapt. It's their "job." And they are amazingly good at it. Moreover, young children don't fret about failure the way that school-age children and adults tend to do. They take detours and setbacks in stride because they know intuitively that such obstacle are a part of the problem solving process. Still, we need to encourage problem solving in children. Whenever possible, this involves letting children find their own ways of reaching their goals. Good parents and other caregivers know when to stand back and let a child figure things out and when to step in and offer the right amount of help. For educators to accept errors, uncertainty, and indirect paths toward solutions is itself a difficult problem because doing so contradicts our ingrained beliefs and expectations about teaching and learning. But problem solving must be understood and promoted if the next generation is to be prepared for the unprecedented challenges (i.e., problems) that it will face.

Critical Thinking involves the ability to collect as much evidence as possible before making decisions which must be based on logical steps and scientific principles. It encompasses the entire process of obtaining, comprehending, analyzing, evaluating, internalizing, and acting upon knowledge and values. Critical thinking involves:

Science is based on observable, repeatable data. The ability to test our hypotheses and to verify the results of other investigators is an important facet of the science investigative process. In addition, problem solving is not an advanced process that is reserved solely for mature learners. Indeed, people of all ages can and must be solvers of problems. Perhaps young children are the most natural problem solvers. Because they continually face circumstances that are novel, they must adapt. It's their "job." And they are amazingly good at it. Moreover, young children don't fret about failure the way that school-age children and adults tend to do. They take detours and setbacks in stride because they know intuitively that such obstacle are a part of the problem solving process. Still, we need to encourage problem solving in children. Whenever possible, this involves letting children find their own ways of reaching their goals. Good parents and other caregivers know when to stand back and let a child figure things out and when to step in and offer the right amount of help. For educators to accept errors, uncertainty, and indirect paths toward solutions is itself a difficult problem because doing so contradicts our ingrained beliefs and expectations about teaching and learning. But problem solving must be understood and promoted if the next generation is to be prepared for the unprecedented challenges (i.e., problems) that it will face.

Creative Thinking is the ability to think "outside the box" but still adhering to the scientific method and scientific principles. Creative thinking works in tandem with critical thinking. Creativity involves the ability to go beyond the schema normally used to approach a problem and change the framework so the problem might appear in a different light. The creative thinker has the ability to consciously shift perspective when viewing a problem so that many different views of the same problem are examined. Critical thinking involves:

Science is based on observable, repeatable data. The ability to test our hypotheses and to verify the results of other investigators is an important facet of the science investigative process.

Creative thinking and critical thinking are sometimes called productive thinking. We often use these together in the planning and designing activities together with the class. During an initial brainstorming phase, critical restraints are minimized to encourage a free creativity in generating lots of ideas, but these are critically examined at an editing phase. It is important that in brainstorming, whether it is in pre hands-on or post hands-on, be free as censoring the ideas as they emerge may stifling creativity. Record all ideas when you brainstorm and edit the ideas when you are discussing using the scientific method. We should not hinder the creative process by analyzing the ideas during the creative phase - this is more appropriately treated with critical thinking in the discussion phase. Critical thinking is like the brakes on a vehicle, and creative thinking is analogous to the accelerator. Some of us are over cautious and "ride" the brakes all the time, other never use the brake… Over use of the brake will get us nowhere and stressed! Over acceleration will get us nowhere fast and probably not in one piece! How many people have you stressed with your "speeding"? A good driver uses the accelerator and the brake wisely. Creative thinking must be balance by critical thinking. Together they often create a tension between tradition and innovation. A good detective uses creative thinking and subsequently evaluates all the evidence using critical thinking.

Lesson A:

Concept: "Sieves have holes which allow the smaller components of mixtures consisting of particles to be separated according to particle size".

Pre Hands-on Activity

Teacher explains that in building a house the builders have a problem. The sand used for plastering the brick walls have become mixed with gravel. In plastering the gravel makes the task difficult as it prevents the mason from creating smooth walls. Pupi;s are presented with the problem to solve

Hands-on Activities:

Inquiry Skill(s): communication, problem solving, creative thinking.

Pupils (in groups of 4) are presented with a mixture of gravel and sand, sieves of different sizes, and bowls. Pupils are asked to try to separate the mixture into sand and gravel.

They plan a procedure and record the results of their activity in the table.

Post Hands-on Activities

Inquiry Skill(s): Making Inferences, critical thinking

Pupils discuss the results. They critically analyze their procedure and make inferences about why the mesh separates the particles of different sizes. The application of sieves in real life is discussed. Use of filter paper and cloth to separate mixtures are discussed.

Lesson B:

Concept: "Sieves have holes which allow the smaller components of mixtures consisting of particles to be separated according to particle size".

Hands-on Activities

Inquiry Skill(s): Observation, communication

Pupils are given a filter paper to separate an undissolved sugar from a solution of sugar. They are instructed to fold the paper in a two half folds and place it in a funnel. Pour the mixture into the funnel and observe the results. Pupils draw the equipment and label it.

Post Hands-on Activities

Inquiry Skill(s): Making Inferences, critical thinking

Pupils discuss the results. They make inferences about why the paper separates the particles from the solution. The application of filtration in real life is discussed. Use of filter paper and cloth to separate mixtures are discussed.