Seminar on TAS for AL

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Seminar on TASfor AL ASL Chemistry
Practical22 October 2005
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Programme

• 900 Registration / Exhibition
• 915 Introduction to Chemistry TAS
• Dr T M Li, HKEAA
• 945 Learning, Teaching Assessment of
  Practical Skills, Assessing Area A, Mr
  W C HO, EDB
• 1045 Break
• 1055 Assessing Techniques, Resources on
  Practical Chemistry Mr W C HO, EDB
• 1145 Experience Sharing Mr C K
  Leung, NTHKY Yuen Long District Sec School
• Mr KM Chan, TWGHs Mrs Wu York Yu Mem
  College

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Why TAS?

• Drawbacks of practical examination(QA VA)
• More relevant and greater variety of expts in TAS
• Convey the excitement and wonder of Chemistry
  through practical work
• Reinforce understanding and knowledge of theory
• Develop practical and generic skills

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Purpose of Assessment

• Assessment for Learning ???????
• Provide information about the progress of
  students in relation to knowledge, skill and
  understanding
• Identify where emphasis needs to be made to the
  next stage of learning

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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 Box
• Assessment Reform Group, UK

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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.

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

• Methodical Working ???????
• correct sequence of operations, efficient use of
  time, etc.
• Experimental Technique
• correct safe handling of apparatus chemicals,
  and carrying out operations (observe students
  directly or based on comparison with target
  values)

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

• Skills in Observation
• read scales on instrument to the correct degree
  of accuracy
• 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??????
• Orderliness

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Assessment in Practice

• Marking scheme
• Overall impression (Descriptors), holistic
• Be objective and unbiased
• Independent assessment of different skills
• Professional Judgement
• Prioritise skills to be assessed

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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)

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Acid-base Titration

• Marks may be allocated by taking into account of
  the following
• Rinses out burette taking care to rinse jet
• Clamps burette vertically
• Fills jet of burette up before starting titration
• Uses pipette filler correctly
• Pipettes exactly 25 cm3 of dilute sodium
  hydroxide
• Transfers exactly 25 cm3 of dilute sodium
  hydroxide to conical flask without spillage
• Adds dilute sulphuric acid in suitable amounts
  from burette
• Continually swirls the flask during the addition
  of the acid
• Works safely
• Works tidily
• (Earl Wilford, Practical Assessment in Advanced
  Chemistry)

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Making Assessment Criteria

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

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Time-out

• ????

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

• Accurate recording of observations
• Present results properly and systematically
• Use correct units and appropriate no. of sig.
  fig.
• Understand principles efficient calculations
  aware of sources of errors in quantitative work
• Recognise the reactions involved draw relevant
  conclusions in qualitative work
• Students ability to plan and carry out experiment

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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 manner
• Students own words and reflect their
  understanding
• Vary regularly the information in the lab manual
  to avoid plagiarism
• Feedback
• grades/marks/comments, helps students know their
  learning progress

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Assessment Activity 2Area B
Criteria Weighting Score
Clear account, proper use of chemical nomenclature terminology, accurate spelling, punctuation and grammar 2 1
Correct efficient calculations 3 1
Appreciation of data and major source of errors 2 0
Satisfactory answers to discussion questions 2 2
Draw valid conclusion by applying knowledge and understanding of Chemistry 1 1
10 5
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What is Practical Work?

• Not merely as a practical activity doing things
• Essentially 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

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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)

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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
  nitrate solution
• Correct order of addition of reagents
• Time from first addition of silver nitrate
  solution or haloalkane
• Time for first precipitate to appear
• Correct relative order of hydrolysis
• Suitable modifications

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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) autonomy
• Increase the opportunities for students to think
  about the data they should collect and their
  presentation

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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)

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Assement Criteria in UK
HK UK
Manipulative Skills (A) Implementing Manipulation
Observation (A) Implementing Recording
Interpretation (B) Analysing Evidence Drawing Conclusions Evaluating Evidence Procedures
Planning (B) Planning (Descriptors, Exemplars)
HKEAA http//www.ocr.org.uk http//www.aqa.org.uk http//www.edexcel.org.uk http//www.nuffieldchemistry.org
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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 activities that test a
  students laboratory thinking skills and use
  problems posed in the laboratory as true
  assessment tools

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Assessing Project Work

• Inquiry-based expts, Investigation, Project
• Encourage students to learn by exploration
• Include designing experiment, investigation and
  written report
• Develop their skills in problem-solving,
  planning, data handling, organisation and
  presentation
• Guidelines for students Nuffield tutorials on
  investigation (http//www.chemistry-react.org/go/T
  opic/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

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Scoring Rubrics to Evaluate Student Inquiry

• Define the end product of inquiry e.g.
  portfolios, research report, laboratory
  practicals and student demonstrations, student
  journals, concept maps
• 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
• Decide who will assign the grade e.g. expert
  judging (supervisors sheet), self-evaluation and
  peer evaluation
• Lunsford E Melear C T (2004) Journal of College
  Science Teaching, Sept, pp.34-38

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Rubric for evaluating a research report
Criteria Absent Absent Excellent 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 _________ Your score _________ Your score _________ Your score _________ Your score _________ Your score _________
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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 (10highest) rate your self on how well you are working with others in your group.
Forster, M Master, G (1996) Projects Assessment
Resource Kit
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Peer Assessment

• Student ______________ has contribute to the
  groups 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 penalty
Habeshaw, S Gibbs, G Habehaw, T (1998)
Interesting ways to assess your students
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Practical Chemistry Resources

• Exemplars of Learning Teaching Activities for
  Sixth Form Chemistry Curriculum,
  http//resources.edb.gov.hk/science/chem.htm
• Resource Book for Sixth-form Practical Chemistry,
  CUHK
• TAS Corner (http//cd.edb.gov.hk/sci)
• ???????????
• Reference Books (Adv Practical Chem, NAS, Classic
  Chem Expts, etc)
• Internet Resources
• Datalogging expts, Diocesan Girls
  Schoolhttp//www.dgs.edu.hk/QEF_Sc/Chem/experimen
  ts.htm
• Journals e.g. Chem Review, Chem 13 News
  (http//sciborg.uwaterloo.ca/chem13news/index.html
  ), Education in Chemistry, ????

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Videos on Practical Chemistry

• Demonstrate a new technique during lab class
• As a resource for students in pre-lab assignments
• As a review of a specific technical procedure
• Quality assurance of laboratory techniques
• http//cd.edb.gov.hk/sci/chemistry/tas/videos.htm

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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 schools
• Constituent Grants of
• Operating Expenses Block Grant ??????????for
  Aided Schools (Adm Circular No. 27/2000 CM
  No.161/2005)
• Subject and Curriculum Block Grant for Government
  Schools ???????????????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 Schools (CM No. 27/2005)

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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 equipment
• Choosing experiments
• Syllabus suggestions, TAS requirements
• Educational value, safety, availability of
  chemicals equipment, teaching time, etc.
• Variety, Cook-book or Inquiry based
• Arrangements
• Tryout of expts, coordination with LTs, oral and
  written instructions to students, distribution of
  chemicals equipment, laboratory reports, etc.
• Students with physical disabilities

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Instant Lab Report

• Post lab reports - focus students attention on
  producing good finished reports
• Reports at the end of practical
• students are likely to work faster, try to make
  more sense of what 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 neatness
• Free students afterwards to do something more
  constructive
• (Habeshaw et al, Interesting Ways to Assess Your
  Students)

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Assessment Enhances Learning if it

• Encourages intrinsic motivation
• Builds confidence
• Gives a sense of ownership and control
• Provides detailed feedback constructively
• Encourages collaboration between students
• Prof. Patricia Broadfoot, U of Bristol

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http//resources.edb.gov.hk/science/chem.htm
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Thank you!