PSLE 2012 - Science

[1girl1boy]

MeKiasuLeh:

IMHO, @verykiasumummy and @atutor2001 answers to the frog/tadpole question would readily be acceptable. I did not read all threads so there might be more worthy ones.


This is a booklet B question, and I believe most questions in booklet B require students to demonstrate their knowledge of Science, it's application, as well as reasoning skill. And for this reason, PLSE markers will be asked to mark \"holistically\", a terminology used widely in the answer key found in RGPS exams marking scheme. Probably RGPS uses the same format (answer key) as MOE or vice versa. I also believe, like in most schools, each paper is marked then verified by another before the final score is set in stone.

How do one tackle such a question? First, we know its biology we are dealing with and one of the first things that should come to mind is that a tadpole is the young of a frog and a frog is an amphibian, both of which are living things that need a conducive habitat to survive in. Next, we ask ourselves a series of questions e.g. Do they live on their own? Does one need to know about life cycle of a frog? Where is the food source of a frog and tadpole? Also, do we need to consider the stages that a tadpole has to go through before being an adult? Articulating the answer would be the challenge but I believe keeping within these premise should be safe and it is best to keep the answer within a natural setting (i.e. avoid throwing disasters, like fire, drought, etc into the mix).

I am inclined to answer this way .....

A frog is an amphibian which lay eggs on water, leaving their young, the tadpole, to survive on their own in its life cycle. Frogs feed mainly on insects and other small creatures that can be found mostly on land whereas tadpoles feed primarily on plants, mainly aquatic plants which can be found mostly in water. Frogs are more agile on land than on water, and this helps them avoid predators and find food better, thus ensuring their survival. On the other hand, tadpoles, which do not resemble their adults particularly in their initial stage of development, has no or ineffective limbs. Therefore, tadpoles are inherently adaptable to water than on land, allowing them to move better to find food and avoid predators. These are the advantages for frog to live on land and for tadpoles to develop into adulthood in water.

How much to write? I will use the space provided in the booklet as a guide. Now, I truly do not know what the right answer is, or will my proposed answer be acceptable. It might just managed to elicit a sly smile from the marker but no marks! But so long as a student keep it within a logical framework and mentioned key things like \"survival\" and \"Food source\" and relate these to land and water and demonstrate what habitat means, I believe he/she should be safe.

For those die die must know 'the right answer' then I suggest he/she tap on VitaMindZ. I heard the folks there used to set PSLE Science questions and the top PSLE girl last year had her tuition in that centre. But for me, I believe a student should practice using his/her own intuition, learn to perform own research, interact with fellow students and consult teachers/parents as much as they can for the real challenge is after P6.

I havent heard about VitaMindZ. I have heard about MindStretcher and Learning Lab.
If I am not wrong, this is a 2 x 1 mark question. Why Why are we thinking so hard to answer this question? We need expert help some more from some previous setters of PSLE? :?

[1girl1boy]

AWSP:

I have a little parody on the question on friction.

A teacher is teaching students John and Mary how to answer a question on friction. (Reference a,b,c).
Teacher: In c, the object is moving down the slope because the gravitational force is greater than friction. Whereas, in b, the gravitional force is less than friction so it is not moving.
John: But teacher, I thought gravitational force is the same no matter how steep is the slope. Does it mean that there is greater gravitational force when we stand on the top of the stairs?
But the teacher cannot teach vectorisation of forces.
Teacher: No, gravitational force is the same on top of the stairs as below. But on the slope, it is greater. TRUST ME. This is PSLE science WANTS you to know. Remember you slide down easier when the slope is steeper.
Teacher: Now in a, there is no movement so there is no friction.
John: But in b, there is also no movement so there is no friction.
Teacher: In b, the gravitational force is greater than on b. TRUST ME. This is PSLE.
During PSLE, the same question came out. (Note this is only a hypothetical play).
John asks Mary: Did you get the question on friction correct? I got confused because I start asking the same questions again.
Mary: Yes, I got it right with a lot TRUST.

Ha Ha, Good one :rotflmao: