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Investigative study
K C Pun(punkc2007@gmail.com)
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Agenda Sharing of IS experience
Preparing for NSS IS
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Students and Trial run for IS 15 – 17 F.5 students (after taking their
HKCEE) Why F.5?
Similar standard for later NSS Year 2
Period: One week in June Drawback:
Some students have to have oral practice during this period of time
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3 investigations to choose Making Your Own
Acid-Base Indicator
How to make it hot?
Which snack is healthier?
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Why students have a choice? Merits:
Individual group Collaboration within the group (More focus) Cannot copy results from other groups
Demerits Less collaboration among groups Less easy to supervise (require more individual
group consultation)
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Schedule (20/6 - 27/6) Searching for and defining questions for investigation
(20/6) [10:30 a.m. - 12:30 p.m.] S s T T
Developing an investigation plan and discuss with the teacher (21/6) [8:30 a.m. - 12:00 noon]
S s T T Conducting the investigation (22/6 - 23/6) [8:30 a.m. -
12:00 noon] S s T T (Safety) Organising and analysing data for presentation
(26/6/2006) [8:30 - 12:00 noon] S s T
Presentations (27/6/2006) [8:30 - 12:00 noon]S T
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Stage 1 & 2: Searching info & Investigation Plan Give some key words
Provision of Article to provoke thought (e.g. Instant Soup)
Booking of MMLC
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Article on instant soup Chinese version: Apple Daily 1 Oct 2006
即 飲 湯 一 搖 即 熱 (Wise News) English version: Soup that heats up itself 29 Se
pt 2006 [Online]
http://www.dailyrecord.co.uk/news/tm_objectid=17839942&method=full&siteid=66633&headline=soup-that-heats-itself-name_page.html (12/4/2007)Info given: 75 ml pot
Chemical rx: calcium oxide + water
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Stage 1 & 2: Searching info & Investigation Plan Discussion
Do not give direct answers
A listener rather than a speaker
Allow time for silence Remind students about
the time frame (possible to finish within 6 – 8 hours)
Remind students to request chemicals / apparatus through laboratory technician
Remind students to write down the safety aspects of the investigation
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Stage 1 & 2: Searching info & Investigation Plan May remind the
students Simple may not be
simple; difficult may not be difficult
Why this method but not the other?
Any assumptions made in the IS
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Questions that may arise Should teachers help the students?
E.g. For salt content, students may not know the concentration to be used. Should teachers give them guidance? If not => not enough time to complete
Each school has its own circumstances. Do you accept failure in getting results? Do the students have enough materials to
report?
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Stages 1 & 2 One group: Heat up a container
Two groups: salt content in snacks
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Stage 3: Conducting the investigation Safety first: Must wear safety goggles Info given to students: Marks will be deducted
for handling apparatus / chemicals unsafely Suggestions:
Keep an eye on the students Safety issues arising:
CaO in enclosed container(The next 3 slides)
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Mounheat as a Cooker
X 2
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Then add 1 of water into the can.
Water
And cover the mouth with the .
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Put this can into where you want to heat.
E.G: Rice and noodles.
After 5 mins, when smoke comes out, the rice is at about 60C.
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Result The container expands.
Accident may occur. Take note on safety aspects of the experiments.
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Stage 3: Conducting the investigation Simple is not simple. Difficult is not difficult. E.g. Determine the salt content
Gravimetric method vs titration method? One group chose gravimetric method and another
group chose titration method
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Stage 4: Organizing and analysing data Booking of MMLC
Discussion (S T: at least 1 time per group)
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Stage 5: Presentation Group I: Salt content (titration method) Group II: Salt content (Gravimetric
method) Group III: Instant heat container
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Questions by teachers Why was this method chosen? Any assumptions made? Difference between sample and
population. Note for irregularities and questioning If you did it again, what would you do? ……….
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Photos: techniques Photos included in their
powerpoint
May reflect their skills
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Students’ reflections
-Team work spirit develop need to cooperate with teammates when
we are doing experiments
-Learn how to plan an experiment
-Know more knowledge about potential hazards of eating snacks
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Preparing for NSS: The Inquiry-based approach Structured inquiry
Guided inquiry
Open inquiryColburn, 2004
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Structured inquiry ~ verification approach May provide step-by-step instruction May not have the data table Students:
Decide what observations to be recorded Figure out the meaning of the data
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Guided inquiry Students
also choose what data to be collected Design the procedure to address the activity’s
main question Students’ procedures and results often
vary A deeper understanding of the content
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Open inquiry Students make almost all the decisions Students:
Think the question for investigation Decide
What data to be collected? How to interpret the data
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Advantages of using a lab-investigative approachSignificant gains in Formulating hypotheses Making assumptions Designing and executing investigations Making observations Recording and analyzing data Synthesizing knowledge Development of openness, responsibility and satisfact
ion(Lechtanski, 2000)
Also important for the current students
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An example to be used before carrying out IS: A carbonate rocket In F.4 (2005 – 2006), teaching
“acids and bases” Given scenario:
You: product designer One day:
water + fizzy drink tablet at the base of film canister (as the rocket) What happens?
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Carbonate rocket But find out:
Knv gdhfgs
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Caesar cipher (Encryption) P-1 Low height.
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A carbonate rocket
Task: To determine the best propellant What chemicals and apparatus would you
use? How can you measure the distance
traveled by the rocket accurately? Prepare a proposal.
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Safety first Avoid the acidic substances (irritating)
touch the skin and into eyes. Avoid the powdered substances get into
eyes. Keep a safe distance from the rocket when
launching it. Ensure the rocket is launched vertically.
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Materials and equipment Chemicals: only provided upon request and te
acher’s approval An electronic balance A weighing bottle / paper A 10 cm3 measuring cylinder Measuring tape (2 m)Do this on next Day!! Have fun andLearn.
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A carbonate rocket
Task: To determine the best propellant What chemicals and apparatus would you
use? How can you measure the distance
traveled by the rocket accurately? Prepare a proposal.
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Summary Carbonate / hydrogen carbonate + acid
carbon dioxide + water + salt Write chemical equations for acid
reactions Proposal for “rocket” design
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Summary How high?
Why? Amount of gas generated? Amount of carbonate-containing substances Concentration of acids ………..
Which method is the best? Height? Amount of chemicals Amount of waste
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Another experiment (IS) to consider From newspaper:
紐利賓納誤導判罰款 維他命 C 含量與標籤不符 14 歲女生小實驗揭大謊言 ( 明報 , 28/3/2007) 聲 稱 維 他 命 C 含 量 是 同 份 量 橙 汁 4 倍
澳 洲 利 賓 納 認 誤 導 (Apple Daily, 22/3/2007) 做 實 驗 狂 質 詢 證 誇 大 維 他 命 C 含 量
華 裔 少 女 踢 爆 利 賓 納 作 假(Apple Daily, 28/3/2007)
Vitamin C determination
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Grouping My situation: Form groups by themselves Depend on individual classes
Teachers should know their classes best
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Preparing for NSS F.5 students after HKCEE : most appropriate ti
me (IS) Can introduce basic investigative studies in F.
4 / F.5 level – for the students to familiarise with SI
Starts from small number of students first A suggestion: May select those students who a
re likely to come back to study F.6 (Paving their way to AL)
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Preparing for NSS What type of reporting?
Powerpoint (Could be marked during presentation)
Poster (Avoid the problem of asking similar questions if the same topic is chosen)
Full report (Avoid the problem of asking similar questions if the same topic is chosen but lack of oral presentation skills)
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Comparing different types of reporting
Written present.skills
Oral present. skills
Marking during present.
Time
Powerpoint s t
Poster (?)
s t
Full report S T
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Final comments Any extra work?
Requirements (less compared with TAS) Students: Greater effort in doing experiments
More experimental work? Should be done Help them to understand Help them to write procedures (In annual reports, often
stated that lack of experimental work) Work with EDB staff Relationship with staff in school
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