Science process skills/Raising Questions
The teacher describes a situation and encourages the students to raise questions regarding the situation with ‘what’, ‘why’, ‘when’ and ‘how’.
I. “We are very much familiar with the terms darkness and light. The absence of light creates darkness. Light is a form of energy always in motion. It can travel through vacuum with a maximum speed of 3 x 108 meter/second which is equivalent to three lakh kilometers per second. In fact nobody can travel than the speed of the light in the whole universe”.
Just like heat, light is a form of energy (the students are likely to ask following questions).
Questions raised by students:
1. How that light is is a form of energy? 2. Why does light travel so fast? 3. If light is a form of energy, can we convert light into heat? 4. How could you tell that the speed of light is 3 x 1010 cm/sec? 5. Do light from different sources have the same speed? 6. Do different colored light travel with same speed?
II. “When a beam of light is incident on a plane surface separating two media, a part of it is returned into the first medium. This phenomenon is called reflection. The surface which reflects most of the light falling on it is called reflecting surface. Reflection is of two kinds, namely, regular reflection and irregular reflection.”
Questions Raised by students:
1. What is reflection? 2. What is reflecting surface? 3. What is regular reflection? 4. What is irregular reflection? 5. What is scattered light?
III. How light rays are reflected by a smooth plane mirror. Consider a light ray, AB, falling on the smooth plane PQ, at the point ‘O’ as shown in the figure. AB is called incident ray, ‘O’ is called point of incidence. Let ‘ON’ be the normal drawn at ‘O’, ∟AUN is called angle of incidence ‘i'. The ray after reflection goes in the direction CD. The ∟DON = r, called angle of reflection> N
P O Q
Questions raised by students:
1. What is the normal? 2. Which represents PQ? 3. What is incident ray? 4. What is reflected ray? 5. Will angle of incidence is equal to angle of reflection? 6. Why should we draw a normal at ‘O’? 7. When the position of ‘PQ’ is changed without disturbing ‘AB’ incident ray, what will happen to the reflected ray? 8. What happens if instead of a plane mirror when a curved mirror is placed in this activity?
Grading is assigned basing on the number of relevant questions raised by the students. Inability to raise any question indicates absence of the skill. Five and more relevant questions may be given ‘A’ grade, 3 – 4 questions ‘B’ grade and 1 – 2 questions ‘C’ grade.
IV. Guess who is in my mind: The teacher tells that some object or person is in his/her mind and the students should identify it/him/her by asking questions to him/her. Teacher gives only ‘yes’ or ‘no’ type answer. Appropriate grade is awarded if a student can arrive at the correct answer with minimum number of questions, without directly guessing the answer. Teacher tells that I am thinking of a metal, guess what it is?
S.No. Student’s Questions Teacher’s Answer 1. Is it domestically used? Yes 2. Is it white in color? No 3. Is it used in making electrical goods? Yes 4. Is it red in color? Yes
Now, the answer is copper metal. Student is given ‘A’ grade.
Note to the teacher: This game should be introduced after teaching the lesson metals and their characteristics.
A question which minimizes the scope of our search can be considered as good question. If a student arrives at an answer with minimum number of good questions will be given ‘A’ grade. If the questions increases, but all are good questions, then ‘B’ grade can be given. If the questions are not good, and the questions are many, or failed to arrive at answer, ‘C’ grade may be given.
Example for ‘B’ grade:
1. Is it hard metal? Yes 2. Is it industrially used? Yes 3. Is it domestically used? Yes 4. Is it white in color? No 5. Can we use it in making alloys? Yes 6. Is it used in making ornaments? Yes 7. Is it a costly metal? No 8. Is it red in color? Yes
It is copper metal.
Example for ‘C’ grade:
1. Is it a soft metal? No 2. Is it a hard metal? Yes 3. Does electricity pass through it? Yes
After such not useful questions he/she may or may not arrive at correct answer, and then he/she may be given ‘C’ grade.
V. Two groups of equal sizes (students) play this game. A member of first group puts a question to the other group and vice-versa and this procedure continues till one group wins. This group game can be altered in many ways by changing the rules of the game depending upon the teacher. (It can be employed for group assessment).
VI. A game can be generated or designed to reinforce learning and also improve the questioning skills by the students. The teacher first poses a problem and asks the students to solve the problem either straight away or by asking some clues. To get the clues the student has to question the teacher. If the clue is very important more marks may be deducted from the student. If the clue is not very significant fewer marks may be deducted.
Example: Teacher demonstrates an experiment and asks the students to find out what is the type of change. The questions may be as follows.
1. How many reactants did you use? 2. How many products are found? 3. Are the reactants elements or compounds or both? 4. Are the products elements, compounds or both? 5. Is there a new substance formed? 6. Give the names of reactants? 7. Give the names of products? 8. Give the formulae of reactants and products?
Grading is assigned basing on the number of relevant questions raised by the student. Inability to raise any question indicates absence of the skill. Five and more relevant questions may be given ‘A’ grade, 3 – 4 questions ‘B’ grade and 1 – 2 questions ‘C’ grade.
VII. Movement of solvent not solute. Molecule through semi-permeable membrane is called osmosis.
This funnel experiment is demonstrated by the teacher. Teacher should ask students to observe it and raise their doubts in the form of questions.
NI – What is that long funnel like glass tube? LO NI – What substances (solutions) have you taken in beaker and the funnel? LO NI – What have you tied to the mouth of the funnel? LO NI – What is a semi-permeable membrane? LO I – What other things/materials may be used as semi-permeable in place of egg membrane? MO I – how can we know that a membrane is semi-permeable? HO I – why there is increase in the level of solution in the funnel column? MO I – Is it necessary to use only thistle funnel to conduct this experiment? HO I – What happens if same level of concentrated solutions is taken in both beaker and funnel? HO I – What is the use of this process? HO I – Is it also useful for animals? HO
Note: NI = Non-investigative; I = Investigative; LO = Lower Order; MO = Middle Order; and HO = Higher Order
Scheme of assessment for raising questions:
It is based on certain criteria like –
1. The number relevant and meaningful questions rose by a child. 2. Of what level are the questions raised, i.e. knowledge (LO), understanding (MO), critical thinking (HO). 3. Any unique and peculiar question(s) apart from direct and routine sort.
Note: Very low grade for irrelevant questions.
No grade if attempt to raise questions is not made. Low grade for irrelevant or lower order – ‘C’ grade Moderate grade for non – investigative or middle order for relevant questions – ‘B’ grade Higher grade for higher order or investigative questions – ‘A’ grade
The same assessment pattern is followed in all other activities under skill of raising questions.
VIII. The process of movement of molecule or ions from a point of high concentration to a point of low concentration till the concentration at both the points becomes equal.
A beaker of water is taken and potassium permanganate or copper sulphate crystals are carefully placed at the bottom of the beaker with water. Ask students to raise their doubts as they observe the experiment.
I – What happens to the crystals? MO NI – Why the water around the crystals is darker in color? MO I – Why water is changing color slowly and gradually? MO I – Can we take sugar crystals in place of KMnO4/CuSO4? HO I – Why the molecules of KMnO4 do not spread suddenly at a time? HO I – When does the movement of molecules of KMnO4 stop in water? HO NI – What happens to the water molecules when the KMnO4 molecules are of motion? MO I – Does this process take place both in plants and animals? MO I – What way is this process useful for plants and animals? MO
IX. The pressure exerted by the water molecules absorbed by root hairs is called root pressure.
Teacher demonstrates the experiment to show root pressure, as shown in the figure and explains how to set up the apparatus.
I – Why the stem is removed in the plant? LO NI – Why the glass tube filled with water attached to the root? MO I – Will the plant survive if the stem is removed? LO NI – Why water level rises in manometer? HO I – What happens if more and more water is absorbed by the plant? HO I – Why color is added to the water in the glass tube? MO I – Why a drop of oil added to the surface of the water in the glass tube? HO I – Will the rise in water level be uniform in all plants and in all seasons or climatic conditions? HO I – How to measure the root pressure? HO I – Is root pressure sufficient to pull water in tall trees/plants HO I – Can we take any other substance in the glass tube instead of water? MO I – How root pressure is useful to plants MO NI – Can we measure the amount of pressure exerted in pressure units instead of volume units? HO
X. Present the graph showing relationship between respiration rate and temperature. Teacher initiates by encouraging students to raise the questions that come to their mind after observation of the graph.
1. Why rate of respiration increases with increase in temperature? MO 2. Why it is highest at 300C? LO 3. Why the rate falls even though temperature is increased? MO 4. Why fruits and vegetables kept in refrigerator do not spoil? HO 5. Do all parts of the plant respire? MO 6. What is the application of this principle into everyday life? HO 7. Why fruits, vegetables get easily spoilt in places of high temperature? HO 8. Does this principle apply to human beings also? HO 9. Why people are active during sunny day? HO 10. Why they become easily exhausted during summer? HO 11. Why are they slow in winter? HO
XI. A chart on N2 – cycle was shown to children and were asked to observe how the nitrogen from atmosphere enters the soil and returns back.
1. What is biological fixation? MO 2. Why do plants take in nitrogen inform of nitrates but not as direct form? HO 3. What is ammonification? HO 4. How can N2 from atmosphere enter into the soil as nitrates? MO 5. Why nitrogen has to change into nitrates? HO
- Teacher explains the biological fixation of nitrogen by rhizobium in legume plants.
1. Can any other bacteria fix nitrogen in similar way? MO 2. Can you name some bacteria that fix nitrogen? MO 3. Is it only the bacteria that fix nitrogen or there any other organisms that do this job? HO 4. Can you show the picture of the organisms? MO
- Next teacher explains how plant and animal get decomposed by bacteria and convert into ammonia.
1. What is ammonification? MO 2. How can ammonia being a gas stay in the soil? MO 3. Why it has to convert into nitrates? HO 4. What is difference between nitrates and nitrites? HO 5. Can you give some examples of nitrates and nitrites? HO
- As different concepts are explained by the teachers about N2 cycles, similar pattern of questions can be raised by the students.