Science process skills/Investigating

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Investigating

The process of investigation starts with hypothesis and ends with acceptance or rejection of the set hypothesis. Assessment of skill of investigation can be done through stepwise questioning either by imagining possible happenings or by performing the actual activity or by both, i.e. either through conceptual frame or through doing.

The steps in investigation:

1. Information needed 2. Sequencing 3. Identification of tools – selection of available tools/designing new tools 4. Procedure 5. Measurement 6. Recording 7. Results/Conclusions

I. Hypothesis: Black body absorbs heat than white.

i) Is it possible to verify it? (introductory question) – Enthusiasm, readiness, curiosity, confidence can be assessed. Note: The possible answers may not be directly useful for assessing the investigating skill but are useful for assessing the readiness of the student.

ii) How can you prove this?

1) Gives broad and clear sketches – ‘A’ grade 2) Gives a broad but rough sketch without specification – ‘B’ grade 3) Gives a defective sketch – ‘C’ grade

Example: The students give the following outlines/sketch.

(1) Take two tins of equal size one coated with black paint and the other with white paint (outside). Equal amount of water is taken in both the tins and placed in sun light for a definite time. The temperature of water in both the tins are measured and compare. If the temperature in the first one is higher it is proved. For this outline ‘A’ grade may be given.

Figure:

Note: In this stage, whether the student is giving relevant information needed for the investigation or not is assessed. The information is generally in the form of broad sketch. The sequencing or giving the stages in correct order is tested in the next step. (Question No. iii).

(2) Take two tins, one coated with black paint and the other with white paint. Take water in both the tins and place them in sun light for same time. The temperature measured and compared. If the temperature in the first one is higher, it is proved. This outline may be given ‘B’ grade.

Note: In this, student ignored equality of size of the tins, equality of amount of water and time and presented the outline.

(3) Take two tins, one coated with black paint and the other with white paint inside. Take water in both tins and place them in sun light for some time. Then measure the temperature of the water in both the tins and compare. If the temperature in the first one is higher it is proved. For this outline ‘C’ grade may be given.

Note: In this, the student mentioned that the tins are painted inside with black and white paints, hence it is defective.


iii) Describe this experiment in various steps/list the various steps.

1) If the sequence is correct/logical – ‘A’ grade 2) If the sequence is with minor deviations which will not harm the experiment – ‘B’ grade 3) Haphazard and illogical sequence which effects the results of the experiment – ‘C’ grade

Note: What is a logical sequence?

Generally, material identification, chalking a correct process and recording the results is the logical sequencing.

iv) The teacher places many apparatus which include the required apparatus to conduct the experiment and asks the student to pick up the required apparatus and asks the student to suggest better apparatus of his/her own design.

Probable student responses and assessment:

a) Suggests/designs correct apparatus of his/her own – ‘A’ grade b) Selects appropriate apparatus – ‘B’ grade c) Selects inappropriate or suggests irrelevant/not up to mark/defectively designed – ‘C’ grade

v) How do you perform this experiment? Give details.

1) If the student presents/describes various steps/procedure of the experiment in a sequential order, with accuracy and by taking necessary precautions – ‘A’ grade. 2) If he/she neglects necessary precautions only – ‘B’ grade. 3) If he/she neglects both occurring and necessary precautions – ‘C’ grade.

vi) What measurement you record in this experiment and when?

1) Gives correct/appropriate measurements at appropriate time with accuracy – ‘A’ grade 2) Not with accuracy – ‘B’ grade 3) Any defect either in measurement or time or both – ‘C’ grade

For example, the students give the following ansers.

1. Temperature of water in both the tins at the time of putting in sun light and immediately after the specific time should be noted – ‘A’ grade 2. Temperature of water in both tins after the time mentioned is over should be taken – ‘B’ grade. (Here immediately after the time is ignored). 3. Untimely measurement/ineffective measurement of temperature indicates – ‘C’ grade

vii) What are the conclusions? How do you arrive at them?

1. Given accurate interpretation using on the results obtained in the experiment at various stages – ‘A’ grade 2. Concludes without proper interpretation of the results – ‘B’ grade 3. Improper interpretation of the obtained results of the experiment – ‘C’ grade

For example:

1) If the student concludes basing on the obtained temperatures and results to the heat observed on the black body then it is considered to be accurate interpretation – ‘A’ grade. 2) If the student concludes without considering all the obtained results then it can be considered as improper interpretation – ‘B’ grade. 3) If the student fails to interpret the obtained results/defective interpretation – ‘C’ grade.

II. Hypothesis: Different birds have different food habits.


i) Is it possible to verify it? Can you say it is true?

Student answers:

1. Yes – there are birds whose food habits differ. Some are herbivorous and some are carnivorous and some others omnivorous – ‘A’ grade 2. Birds are different so they take different food items – ‘B’ grade 3. All birds take food – ‘C’ grade

Note: This is to verify enthusiasm, readiness, curiosity or confidence of the student.

ii) How do you prove?

1. Brief description – ‘C’ grade 2. Moderate description – ‘B’ grade 3. Clear description – ‘A’ grade

iii) Specify the steps in a sequential manner

Imitation question if rises about: 1. Domestic, common and rare birds – ‘A’ grade 2. Domestic and common birds – ‘B’ grade 3. Domestic birds – ‘C’ grade iv) Tools used by the children for investigation: 1. Binoculars, net and specimens – ‘B’ grade 2. Net, pictures and specimens – ‘C’ grade 3. Sequential use of tools along with optimal thinking and use of latest sophisticated – ‘A’ grade

v) Procedure: How do you perform the experiment?

1. Observe available pictures, specimens, uses binoculars, finally he/she will go out observing birds – ‘A’ grade 2. Observes common animals, pictures and try for rare birds – ‘B’ grade 3. He/she will observe only birds in his/her neighborhood – ‘C’ grade

vi) Recording: What measurement you record in this experiment and when?

Student prepares a tabular form for observation made and records them.

S.No. Common Birds Name Legs/Wings/Features General Characteristics Rare Birds Name Legs/Wings/Features General Characteristics 1. 2. 3.

1. Lists out the names and general characters of common birds and rare birds – ‘B’ grade 2. Lists out only common birds in the neighborhood – ‘C’ grade 3. He/she will not only list the birds but he/she can try to classify them according to different species – ‘A’ grade

Uses following table to record the said observations:

S. No. Name of the bird Color/Beak/Features Type of Food Parental Care Non-Parental Care Flight Flightless Migration Non-migration 1. 2. 3. 4. 5.

vii) Results: What are the conclusions? How do you arrive at them?

1. Based on the results/observations classify birds into different groups, depending on their food habits as herbivores, carnivores and omnivores – ‘B’ grade 2. He/she will classify them as plant eating and flesh eating – ‘C’ grade 3. Pigeon eats seeds along with small stones as it is required for digestion. Sparrow eats worms. Parrot eats soft fruits. Some birds show parental care also – ‘A’ grade

Similarly other striking features of birds and their study can be evaluated effectively.

Note: Examine the following: 1) Adequacy of results 2) Mode of representation of the results based on these criteria assessment is made 3) Student compares the arrived results to the original statement of hypothesis

Assessment:

1. List of the common characters of some birds and rare birds which are non – migratory – ‘B’ grade 2. Mention the different beaks and food habits of common flightless birds – ‘B’ grade 3. Find out the green color and blue color birds with red and brown beaks – ‘B’ grade 4. Mention few migratory birds with parental care – ‘A’ grade 5. List the common birds with head crowns – ‘B’ grade 6. Mention the common food of that birds eat in their surroundings – ‘C’ grade 7. Mention the habitats of few common birds they come across daily – ‘C’ grade



cateory:Science process skill/Investigation/Evaluation