IB Internal Assessment (Lab) Scoring

CONCLUSION & EVALUATION (CE)

DCP- Aspect 1Concluding

Complete/2 States a conclusion, with justification, based on a reasonable interpretation of the data.

Partial/1 States a conclusion based on a reasonable interpretation of the data.

Not at all/0 States no conclusion OR the conclusion is based on an unreasonable interpretation of the data.

Asp1: States a conclusion, with justification, based on a reasonable interpretation of the data.• Not evaluated but… restate the research question

for the moderator (IB grader)• Do not explain/list the steps of the procedure.• State all final processed data with units– Your personal group data is not discussed here!– If you have 5 levels of IDV, then you will have 5 numbers

(with units) to report.• EXPLAIN why the lab produced these results– This is where most students struggle.– Provide citations/references for any information you had

to look up or research as a footnote.

What do you mean by “explain?”

• “explain”- Make (an idea, situation, or problem) clear to someone by describing it in more detail or revealing relevant facts or ideas.

• Detail! – For example, if asked why your Elodea

doesn’t grow as well in the dark vs. the light, you need to discuss the Light Dependent Reactions in detail (light exciting electrons in chlorophyll-a, ETC, formation of ATP & NADPH) as well as Light Independent Reactions (ATP & NADPH used to reduce CO2 into glucose which can then be used by plant cells mitochondria for growth)

– Be sure to provide references for where you looked this information up again

Scoring Practice: Read this example.

This Asp 1 earned a…

• Didn’t list processed data (rates with units)

• “in direct proportion” is not correct

• No references!

What was good?• discussed warmer

temp’s possibly leading to denaturing of enzymes

1 Why?

DESIGN- Aspect 2Evaluating Procedure(s)

Complete/2 Evaluates weaknesses and limitations.

Partial/1 Identifies some weaknesses and limitations, but the evaluation is weak or missing.

Not at all/0 Identifies irrelevant weaknesses and limitations.

Asp 2: Evaluates weaknesses and limitations

• These are procedural errors• Think about the procedure & what you did to

conduct the lab. Was there anything not controlled?– Ex: different brands of fans blowing to simulate

wind– Ex: Different brands of cleaner used if trying to

disinfect an area– Ex: Different amount of cleaner used if trying to

disinfect an area– Ex: used potato cells from 2 different potatoes

• Was there something that would lead to your raw data or final processed data to not be as accurate as it could be?– Ex: not enough trials– Ex: not coming in at the same time everyday to

collect raw data in an on going experiment (also a control issue)

• “Weaknesses” are NOT human errors!!– Do not admit that you can’t

count or read a number on a graduated cylinder

– The scale, timer, graduated cylinder are plenty accurate enough!

• You must explain why they are errors AND what affect they would have on your final, processed data

Score: ? Score: 1 Why?

Why did Asp 2 score a “1/partial.”

• need to discuss the uneven distribution of temperatures written into the procedure

• controls did not specify that maggots come from the same batch/be the same age (what effect could this have on processed data?)

What was good?• it did discuss the problem with maggots not

going straight

DESIGN- Aspect 3Improving the Investigation

Complete/2 Suggests realistic improvements in respect of identified weaknesses and limitations.

Partial/1 Suggests only superficial improvements.

Not at all/0 Suggests unrealistic improvements.

Asp 3: Suggests realistic improvement to weaknesses and limitations

• How would you re-write the procedure to fix each error? • Be specific!

– Ex: If more trials are needed, then state exactly how many more trials

– Ex: if you want only 1 type of cleaner to be used as a disinfectant, then state exactly which one, exactly how much, & for exactly how long it is to be used.

• Realistic: consider the equipment we have here (or would reasonably have in a school)– If you want to enlarge an image to make it easier to see/count,

we have dissecting & light microscopes, magnifying glasses, cameras & computers. We do NOT have an electron microscope.

• You must also explain how this will fix the error.

Score: ? Score: 1 Why?

Why did Asp 3 score a “1/partial.”

• didn’t fix the uneven distribution of temperatures• Why wasn’t 10 trials sufficient? If it wasn’t, then this

should have been discussed as an error & then specify exactly how many trials should have been done

What was good?• it modified procedure so that the experimenter

would not include trials where the maggot didn’t go straight