Seminar on TASfor AL & ASL Chemistry Practical

22 October 2005

Programme

9:00 Registration / Exhibition 9:15 Introduction to Chemistry TAS Dr T M Li, HKEAA 9:45 Learning, Teaching & Assessment of Practical Skills, Assessing Area A, Mr W C HO, EMB10:45 Break 10:55 Assessing Techniques, Resources on Practical Chemistry Mr W C HO, EMB11:45 Experience Sharing Mr C K Leung, NTHKY Yuen Long District Sec School Mr KM Chan, TWGHs Mrs Wu York Yu Mem College

Why TAS?

Drawbacks of practical examination(QA & VA)More relevant and greater variety of expts in TAS Convey the excitement and wonder of Chemi

stry through practical work Reinforce understanding and knowledge of t

heory Develop practical and generic skills

Purpose of Assessment

Assessment for Learning 促進學習的評估 Provide information about the progress of st

udents in relation to knowledge, skill and understanding

Identify where emphasis needs to be made to the next stage of learning

Learning

Teaching

Assessment

Improve Learning through Assessment

Key factors identified by research: the provision of effective feedback to pupils; the active involvement of pupils in their own learning; adjusting teaching to take account of the results of

assessment; a recognition of the profound influence assessment has

on the motivation and self-esteem of pupils, both of which are crucial influences on learning;

the need for pupils to be able to assess themselves and understand how to improve.

Assessment for Learning: Beyond the Black BoxAssessment Reform Group, UK

Teaching vs Assessment

Which goes first?Teach to learn teaching goes before assessment provide sufficient instructions and

practice relate practical to theory arrange practical as and when appropriate provide feedback for learning

e.g post hoc discussions on experimental results, procedures, etc.

Criteria in Assessing Area A/.. Manipulative and observation skills, general bench performance

Methodical Working 有條不紊的工作 correct sequence of operations, efficient use

of time, etc.Experimental Technique correct & safe handling of apparatus & chemi

cals, and carrying out operations (observe students directly or based on comparison with target values)

Criteria in Assessing Area A/.. Manipulative and observation skills, general bench performance

Skills in Observation read scales on instrument to the correct degree of ac

curacy correct observations (dichotomous judgement) recognise relevant and irrelevant observations use a control to tell whether a change has occurred

(oral questions/written record)

Manual dexterity手法熟練程度 Orderliness

Assessment in Practice

Marking schemeOverall impression (Descriptors), holisticBe objective and unbiasedIndependent assessment of different skillsProfessional JudgementPrioritise skills to be assessed

Making Assessment Criteria /..

5 major criteria for Ability Area A Operation of a single piece of apparatus Carrying out experimental procedures Reading and measurements of different

instruments / apparatus Observational skills General bench performance

depends on the experimental situations (e.g. Analysis of SO2 in Wine)

Acid-base Titration

Marks may be allocated by taking into account of the following:Rinses out burette taking care to rinse jetClamps burette verticallyFills jet of burette up before starting titrationUses pipette filler correctlyPipettes exactly 25 cm3 of dilute sodium hydroxideTransfers exactly 25 cm3 of dilute sodium hydroxide to conical flask without spillageAdds dilute sulphuric acid in suitable amounts from buretteContinually swirls the flask during the addition of the acidWorks safelyWorks tidily

(Earl & Wilford, Practical Assessment in Advanced Chemistry)

Making Assessment Criteria

Assessment Activity #1Cross check with general descriptor criteriaBetter for teachers to develop their own set of assessment criteria to promote teacher professionalismAssessment Grid for a no. of students in an assessment occasion

Time-out

休息時間

Criteria in Assessing Area B/..Presentation of data, interpretation of results, planning of expts

Accurate recording of observationsPresent results properly and systematically Use correct units and appropriate no. of sig. fig.Understand principles; efficient calculations; & aware of sources of errors in quantitative workRecognise the reactions involved & draw relevant conclusions in qualitative workStudent’s ability to plan and carry out experiment

Assessing Area B/..Presentation of data, interpretation of results, planning of expts

Assessed by written reports, questioning, short quiz etc.

Train students to organise and present their ideas in a logical and systematic mannerStudents’ own words and reflect their understandingVary regularly the information in the lab manual to avoid plagiarismFeedback grades/marks/comments, helps students know their

learning progress

What is Practical Work?

Not merely as a practical activity – doing thingsEssentially to be about thinking trying to understand the relations between evidence

and theory stimulate and challenge pupils

Cognitive skills: Recall Understanding (explain) Higher Skills (analysis, synthesis & evaluation)

Example: Heat of Hydration of CuSO4

Comparison of the rates of hydrolysis of haloalkanes

Experiment Instructions:Devise a small scale experiment to compare the rates of hydrolysis of the bromoalkanes given.Write a brief plan of the experiment you intend to carry out and hand this to your teacher. Carry out the experiment and using the evidence you obtain place the three compounds in order of increasing rate of reaction. At the conclusion of your experiment note any modifications you made while carrying it out and hand these to your teacher along with your derived order of reaction.

(Earl & Wilford, Practical Assessment in Advanced Chemistry)

Comparison of the rates of hydrolysis of haloalkanes

Assessment Criteria: Eye protection Ethanol is used as a common solvent Equal quantities of ethanol, haloalkanes, silver nitrat

e solution Correct order of addition of reagents Time from first addition of silver nitrate solution or ha

loalkane Time for first precipitate to appear Correct relative order of hydrolysis Suitable modifications

Incorporating Inquiry into Expts

Choose expts that address simple concepts can be completed using familiar equipment can be safely conducted e.g. microscale where the data can be pooled by the class and leads

to final results Inquiry - an active engaging process that mimics the work done by actual scientists (NSTA)Require students to design some or all of the procedures (ownership and motivation): autonomyIncrease the opportunities for students to think about the data they should collect and their presentation

Inquiry-based Experiments

Exemplar Individual Investigations, Salters Advanced Chemistry (http://www.york.ac.uk/org/seg/salters/chemistry/investigation/investigations.htm)

Inquiry-base Experiments in Chemistry Calculating Heat of Solution Identifying Unknown Solutions Brown versus White Eggshells Effect of Temp on the Rate of a Clock Reaction

Creative Problem Solving in Chemistry A Black Solid (C & CuO) Making Copper (from Cu(NO3)2)

Assement Criteria in UK

HK UKManipulative Skills (A) Implementing – Manipulation

Observation (A) Implementing – Recording

Interpretation (B) Analysing Evidence & Drawing Conclusions

Evaluating Evidence & ProceduresPlanning (B) Planning (Descriptors, Exemplars)

HKEAA

http://www.ocr.org.ukhttp://www.aqa.org.ukhttp://www.edexcel.org.ukhttp://www.nuffieldchemistry.org

Microscale Chemistry Expts

R. G. Silberman & L. T. Eubanks. (1996). ACS Small-scale Laboratory Assessment Activities. ACS.Microscale equipment and methods reduce time and expense become possible to develop activ

ities that test a students’ “laboratory thinking skills” and use problems posed in the laboratory as true assessment tools

Assessing Project Work

Inquiry-based expts, Investigation, ProjectEncourage students to learn by exploration Include designing experiment, investigation and written reportDevelop their skills in problem-solving, planning, data handling, organisation and presentationGuidelines for students; Nuffield tutorials on investigation (http://www.chemistry-react.org/go/Topic/Default_4.html)Criteria in IS: proposal & plan (15%), Process (30%), Report writing & conclusion (30%), Evaluation and reflection (15%), Attitude (10%)Each project equivalent to a max of 3 expts (1 A & 1 B) 1 report for each group work, request presentation for assessment B of individual students

Scoring Rubrics to Evaluate Student Inquiry

1. Define the end product of inquiry e.g. portfolios, research report, laboratory practicals and student demonstrations, student journals, concept maps

2. Decide criteria and weight: expect tasks, behaviours, and skills and setting standard levels at which students must perform; eliminates or reduces guesswork on students’ part concerning how they will be graded

3. Decide who will assign the grade e.g. expert judging (supervisor’s sheet), self-evaluation and peer evaluation

Lunsford E & Melear C T (2004) Journal of College Science Teaching, Sept, pp.34-38

Rubric for evaluating a research report

Criteria Absent Excellent

Researchable question clearly stated 0 2 4 6 8 10

Hypothesis clearly stated 0 2 4 6 8 10

Pertinent literature reviewed 0 4 8 12 16 20

Methods, procedure, and terminology clearly described

0 4 8 12 16 20

Data presented in tables, charts or graphs 0 2 4 6 8 10

At least five published references used 0 1 2 3 4 5

References cited in paper 0 1 2 3 4 5

Bibliography included 0 1 2 3 4 5

Good grammar and punctuation used 0 2 4 6 8 10

Paper turned in on time 0 1 2 3 4 5

Maximum score = 100 points Your score =_________

Student Self-assessment

Less than others

Same as others

More than others

How much did you contribute to your groups’ project?

Did you offer ideas?

Did you accept ideas from the group?

On a scale of 1-10 (10=highest) rate your self on how well you are working with others in your group.

Forster, M & Master, G (1996) Projects Assessment Resource Kit

Peer Assessment

Student ______________ has contribute to the group’s work in the following ways:

Major contribution

Some contribution

Little contribution

Leadership and direction

0 -1 -2

Organisation and managemnet

0 -1 -2

Ideas and suggestions 0 -1 -2

Data collection 0 -2 -4

Data analysis 0 -2 -4

Report writing 0 -3 -6

Total penaltyHabeshaw, S & Gibbs, G & Habehaw, T (1998) Interesting ways to assess your students

Practical Chemistry Resources

Exemplars of Learning & Teaching Activities for Sixth Form Chemistry Curriculum, http://resources.emb.gov.hk/~science/chem.htm Resource Book for Sixth-form Practical Chemistry, CUHKTAS Corner (http://cd.emb.gov.hk/sci) 高級程度化學實驗資料冊 Reference Books (Adv Practical Chem, NAS, Classic Chem Expts, e

tc) Internet Resources

Datalogging expts, Diocesan Girls’ Schoolhttp://www.dgs.edu.hk/QEF_Sc/Chem/experiments.htmJournals e.g. Chem Review, Chem 13 News (http://sciborg.uwaterloo.ca/chem13news/index.html), Education in Chemistry, 化學教學

Videos on Practical Chemistry

Demonstrate a new technique during lab classAs a resource for students in pre-lab assignmentsAs a review of a specific technical procedureQuality assurance of laboratory techniqueshttp://cd.emb.gov.hk/sci/chemistry/tas/videos.htm

Recurrent Grants for TAS

Purpose Purchase of chemicals, glassware and consumable items Minor repair/replacement of advanced level chemistry equipment

Eligible for government, aided and caput schoolsConstituent Grants of: Operating Expenses Block Grant 「營辦開支整筆津貼」

for Aided Schools (Adm Circular No. 27/2000 & CM No.161/2005) Subject and Curriculum Block Grant for Government Schools

「官立學校科目及課程整筆津貼」School Finance & Account Circular No.2/2000

Provisional payment and adjustment AL: HK$ 2,483 per class per annum (2005/06) ASL: HK$ 1,621 per class per annum (2005/06)

Split-class Teaching in Sixth Form Estimates for 2005/06: Applications for Grants : Aided Secondary Scho

ols (CM No. 27/2005)

Operating TAS

How much should students be informed?Application for operation of new course (via REO) and 1st participation in public examination (via HKEAA)Laboratory facilities and equipmentChoosing experiments Syllabus suggestions, TAS requirements Educational value, safety, availability of chemicals & equipmen

t, teaching time, etc. Variety, Cook-book or Inquiry based

Arrangements Tryout of expts, coordination with LTs, oral and written instruct

ions to students, distribution of chemicals & equipment, laboratory reports, etc.

Students with physical disabilities

Instant Lab Report

Post lab reports - focus students’ attention on producing good finished reportsReports at the end of practical students are likely to work faster, try to make more sense of wha

t they are doing, make more observations and record them in better organised notes, and take more care when recording data, pick up obvious errors, time to do the work again and correct it

Adjust the assessment criteria so that full recording of procedures and results will carry more weight than neatnessFree students afterwards to do something more constructive

(Habeshaw et al, Interesting Ways to Assess Your Students)

Assessment Enhances Learning if it:

Encourages intrinsic motivationBuilds confidenceGives a sense of ownership and controlProvides detailed feedback constructivelyEncourages collaboration between students

Prof. Patricia Broadfoot, U of Bristol

http://resources.emb.gov.hk/~science/chem.htm

Thank you!