ASSESSING PRACTICAL WORK IN THE UNDERGRADUATE TEACHING LABORATORIES

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ASSESSING PRACTICAL WORK IN THE UNDERGRADUATE
TEACHING LABORATORIES

• Phil King

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Contents

• Introduction
• How we used to assess practical work
• Why we changed the way we assess practical work
• How we changed the way we assess practical work
• Group Work
• Summary
• Questions

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How we used to assess practical work

• Traditional laboratory reports.
• Mark out of 10 which includes the following
  components
• product yield,
• observations and equations,
• quality of written report,
• answers to questions.

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Advantages of laboratory reports

• Improves written communication skills
• -writing in a scientific manner
• -presenting experimental data.
• Encourages students to think about the experiment
  they have carried out.
• Prepares students for life in a research
  laboratory.

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Disadvantages of laboratory reports

• Very little formal training given to students
  about how to write an experimental report.
• Little agreement between scientific branches and
  disciplines as to what a report should include.
• Often just copy the experimental method in the
  manual.

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Disadvantages of laboratory reports

• A lot of work for the students.
• Report writing is over-assessed (over the course
  of their three year degree the students have to
  write almost 100 reports).
• A lot of work for staff (marking).
• Large student numbers make it difficult to give
  informative feedback sufficiently quickly.
• Written communication skills and answers to
  questions are often assessed more than practical
  skills.

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How we assess practical work now

• Laboratory classes are now assessed through a
  mixture of answer sheets and laboratory reports.
• The writing of experimental reports is phased in
  over the three years of the degree course.
• First year students mainly complete answer
  sheets.
• Second year students have a more even mixture of
  answer sheets and written reports.
• Third year students mainly produce full reports.

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Designing answer sheets

• Answer sheets have the same design for both first
  and second year laboratories.
• Answer sheets have boxes for students to write
  their answers in.
• Each box has a mark associated with it so the
  students have an idea of the mark scheme.
• In each box the students are told exactly what
  information is required from them (i.e. yield
  calculation, observations, equations, answer to a
  question, etc.).

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Designing answer sheets

• At the end of the sheet the students are told
  which products they are required to hand in for
  marking and how many marks are assigned to the
  quality of the product.
• If the experiment involves spectroscopy the
  students are told at the start of the script
  which spectra they need to attach to the answer
  sheet.

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Designing answer sheets

• For synthesis-based experiments a lot of the
  marks are assigned to product quality and yield
  (separate).
• For spectroscopy-based experiments a lot of the
  marks are assigned to quality of spectra and
  interpretation of the spectroscopic data
  (separate).
• Experiments that test observational skills have
  mark schemes weighted towards the students
  observations and their chemical interpretation.
• Very few marks for answering theoretical
  questions.

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What are we trying to assess?

• First Year Undergraduate Teaching Laboratories
• Basic practical skills
• synthetic skills
• observational skills
• use of lab equipment/handling chemicals
• Ability to carry out yield and mole calculations
• Basic understanding of the experiment

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What are we trying to assess?

• Second Year Undergraduate Teaching Laboratories
• Experiments more complicated so more demand on
  technical skills.
• Students are often asked questions relating to
  the experimental procedure (reaction conditions,
  reagents, etc.) to test their understanding.
• Students required to make a more detailed
  analysis of spectroscopic data.
• Students asked to explain any differences between
  expected theoretical data and experimental
  results.

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Advantages of answer sheets

• Act as a guide for the students during the
  experiment (particularly in the first year).
• Less time consuming for the students (allows them
  to focus on interpreting data rather than writing
  report).
• Detailed marking scheme makes making easier
• -speeds up feedback process
• -increases consistency.

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Advantages of answer sheets

• Use of boxes with marks in makes mark scheme more
  transparent so students can see where they lost
  or gained marks.
• Assigning marks to the boxes makes you think
  before you add unnecessary questions!
• Writing full reports takes on more of a
  significance for the students as they dont do
  as many and are generally worth double marks
  (greater effort made).

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Advantages of answer sheets

• In synthetic experiments students much more
  focused on getting quality sample as worth a
  significant proportion of marks.
• In spectroscopic experiments students more
  focused on getting quality spectra to gain higher
  marks.
• Use of boxes allows the students to handle
  complicated data in a step-by-step fashion
  (particularly important when they are not used to
  handling experimental data).

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Disadvantages of answer sheets

• Can be seen as dumbing down.
• Does not improve written communication skills.
• Easier to copy from a friend.

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Other assessment methods?

• In groups discuss other methods of assessing
  teaching labs
• Take into account all the factors that we have
  already discussed
• What are the main advantages of your new
  assessment method?

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Other assessment methods?

• Group Assessment
• poster
• oral presentation
• group written report
• Peer Assessment

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Summary

• Writing of laboratory reports is over assessed.
• Should be assessing the students practical skills
  (synthesis, data recording and interpretation,
  etc).
• Have made a conscious effort to gradually phase
  in the writing of reports throughout the degree.
• This is done through the use of answer sheets for
  the recording and interpretation of the
  experimental data.
• Answers sheets are designed to reward those
  students with superior practical skills.