177-190 This paper is available online at http://stdb.hnue.edu.vn ASSESSMENT OF THE VIETNAMESE STUDENTS' EXPERIMENTAL CAPACITY WHEN USING EXPERIMENTS IN TEACHING HIGH SCHOOLS CHEMISTRY
Trang 1Educational Sciences, 2021, Volume 66, Issue 5A, pp 177-190
This paper is available online at http://stdb.hnue.edu.vn
ASSESSMENT OF THE VIETNAMESE STUDENTS' EXPERIMENTAL CAPACITY WHEN USING EXPERIMENTS IN TEACHING HIGH SCHOOLS CHEMISTRY
Pham Thi Binh1*, Le Thi Phuong Lam2 and Nguyen Thi Thuy Trang3
1 Faculty of Chemistry, Hanoi National University of Education
2 Thanh Phuoc High School, Ben Tre province 3
Faculty of Chemistry, University of Education, Hue University
Abstract Vietnam's new general education curriculum was just released in 2018, focusing
on developing students' qualities and capabilities Chemistry is an experimental science, thus developing and assessing students' experimental competence in teaching chemistry is a very important task Based on the experimental competence scale, the article introduced and illustrated the assessment tools for this competence including student worksheets, observation sheets, and special tests To pilot evaluation tools, we use specifically pre-test, post-test, and worksheets affecting 63 students in grade 12 of 2 high schools in Ben Tre Province, Vietnam to collect evidence to assess students' experimental competence Thereby assessing the feasibility and effectiveness of constructed tools
Keywords: assessment, assessment tools, chemistry teaching, experiment, experimental
competence
1 Introduction
Depending on the competency components, the competence manifestations as well as the specific teaching activities, teachers choose appropriate assessment tools
There have been quite a few different studies on experimental competence Experimental competence describes some of the most important procedures, processes, and methods that scientists use when constructing knowledge and solving experimental problems [1], or it refers only to problems with an authentic hands-on interaction, involving scientific questions as well
as engineering tasks [2] Weinert defined the conception of experimental competence with the meaning “the ability to meet a complex demand successfully or carry out a complex activity or task” [3] We define experimental competence refer to the ability of students to propose, plan and use experimental instruments and chemicals to successfully conduct chemical experiments;
Observe, describe phenomena, collect data and process them to draw the necessary conclusions
With this meaning, according to the framework of competence constructed from Woods
and Griffin [4], the experimental competence included 4 capabilities: (i) identify the purpose of the experiment, (ii) design an experimental investigation, (iii) do experiment, analyze and (iv) interpret experimental data 10 indicative behaviors of these four capabilities make logical reasoning to find out what to investigate, identify which physics quantity should be measured or which phenomena should choose equipment to make a measurement, describe experimental design, identify real equipment to make measurement, use available equipment to construct measurement,
Received October 11, 2021 Revised November 26, 2021 Accepted December 6, 2021
Contact Pham Thi Binh, e-mail address: ptbinh@hnue.edu.vn
Trang 2collect experimental data, analyze experimental data, interpret experimental data, evaluate and identify shortcomings in an experimental design and suggest specific improvements
Lucila Giammatteo showed assessment tools for experimental disciplinary competencies, including 4 capabilities; and 9 performance indicators, and the authors used rubrics as tools for measuring Experimental competence [5]
An analysis of the past Chemistry examination papers taken in KCSE reveals that the papers test students’ competencies in various aspects of Cognitive Science Process Skill of Evaluation (CSPSE) by Zephania O Anditi [6] It was hypothesized that school characteristics could be influencing students’ acquisition of various aspects of CSPSE In which, cognitive Science Process Skills are process skills which are concerned with students’ intellectual abilities Examples of such process skills are planning, hypothesizing, interpreting, evaluating, and predicting
In Vietnam, there have also been a number of works on research and development of students’ experimental capacity in natural science, specifically focusing on Physics and Chemistry by authors such as Nguyen Van Bien [7], Xaypaseuth Vylaychit et al [8], Tran Thi Thanh Thu [9], Nguyen Thi Dieu Linh et al [10], Dang Thi Oanh et al [11], Nguyen Thi Kim Anh [12],
Le Thi Phuong Lam [13], etc Each work offers its rationality in terms of components, quality criteria, and expression levels of experimental competence The authors analyzed in detail the relationship between the steps in the process of using experiments with the development of experimental capacity for students, thereby proposing methods of using active experiments The use of experiments in teaching chemistry has many limitations such as: in terms of facilities, teachers only use experimental videos or describe and introduce in words; about the method of use, using the experiment according to the illustration, or according to the simple research process (the teacher asks the problem and does the experiment for the students to observe the student does the experiment, state the phenomenon and write the chemical equation) Students are not active and participate much in the proposal and construction of experiments in the way
of real research and discovery, but still rely heavily on the arrangement of teachers There are different methods of using experiments to discover knowledge depending on the program's goals, content, and knowledge logic
2 Content
2.1 Experimental competence framework
In this study, the experimental competence scale included 4 behaviors capabilities similar
to the study of Woods et al [4] But we used only 9 indicative, and quality criteria which are presented at three levels Specifically, 4 manifestations of experimental competence are presented in Figure 1, and criteria as well as descriptions of students' achievement level for each criterion are presented in Table 1 The students' experimental competencies were developed through the activities that students use experiments to explore and discover new knowledge The specific process is presented in Figure 1
Based on the students’ activity progress in Figure 1 to determine experimental competency has 9 behavioral indicators And quality criteria are presented at three levels Instead of describing the usual 4 quality criteria, this study only built 3 quality criteria for each behavioral indicator in the experimental competency scale for the following reasons: (1) difference in the 3-level description will be clearer, more suitable for Vietnamese teachers, (2) Vietnamese teachers' assessment skills according to the criteria are not proficient, so they will be confused with the 4-level description , and (3) the number of students in a class in Vietnam is quite large (about 40-45 students), so it is difficult to observe every small detail of the behavior
Trang 3Figure 1 Process of exploring, discovering new knowledge based on experiments
Figure 2 Components of experimental competence
Components, behavioral indicators, and quality criteria of experimental competency are described in Figure 2 and Table 1 Based on the description in Table 1 to evaluate students' experimental competency
Table 1 Experimental competence scale
Identify the experiment
1 Identify the purpose
of the experiment
Level 1: Determine the purpose of the experiment is not reasonable
Level 2: Determine the purpose of the experiment is reasonable but incomplete
Level 3: Determine the purpose of the experiment properly and fully
Trang 42 Formulate scientific
predictions/hypotheses
Level 1: Make scientific predictions/hypotheses but not reasonable
Level 2: Make reasonable scientific predictions/hypotheses but not complete
Level 3: Make reasonable scientific predictions/hypotheses, full
Proposing experimental plans
3 Identify tools and
chemicals needed
Level 1: Identify some necessary tools and chemicals
Level 2: Identify the most essential tools and chemicals
Level 3: Determine accurately, and fully necessary tools and chemicals
4 Identify the steps for
conducting experiments
Level 1: Identify a few steps to conduct experiments
Level 2: Identify most of the experimental steps
Level 3: Define accurate, detailed and complete steps in conducting experiments
Do experiment and collect experimental data
5 Follow safety rules
experiments
Level 1: Implement some safety rules when doing experiments Level 2: Implement most safety rules when doing experiments Level 3: Fully comply with the safety rules when experimenting
experimental
manipulations
Level 1: Performed awkwardly, not yet proficient while performing the experiment
Level 2: Most experiments were performed correctly but still slowly
Level 3: Perform experimental manipulations in a proficient, technically correct manner
7 Collect experimental
data
Level 1: Collect some necessary experimental data
Level 2: Collect the majority of the necessary experimental data Level 3: Collect fully and accurately the necessary experimental data
Analyze experimental results and draw conclusions
experimental data
Level 1: Analyze a few experimental data
Level 2: Analysis of most experimental data
Level 3: Analyze test data fully and accurately
9 Draw scientific
conclusions
Level 1: Draw scientific conclusions but not true
Level 2: Draw scientific conclusions that are not accurate, complete, and clear
Level 3: Draw scientific conclusions that are accurate, complete, and clear
Trang 52.2 Methodology
Research Goal
Design appropriate assessment tools to gather evidence that assesses each performance indicator of experimental competence, thereby developing and assessing students' experimental
competencies
Research question
How to design assessment tools to students demonstrate manifestations of experimental competence and teachers can collect evidence conveniently?
Research method
Using methods literature review
To pilot evaluation tools, we use specifically pre-test, post-test, and two worksheets of the chemical properties of glucose, fructose and the chemical properties of sucrose, starch, and cellulose content, Chapter 2, Chemistry grade 12 affecting 63 12th grade students of 2 high schools (Le Hoang Chieu High School and Le Quy Don High School) in Ben Tre province, Vietnam to collect evidence to assess students' experimental competence
Specific test (on paper) Worksheet, Rubric (in activities that students
perform experiments to explore and discover knowledge)
Specific test (on paper)
In which, the pre-and post-experimental tests, study cards were built with similar tasks to easily compare the students' progress through the manifestations of experimental capacity Answers, scores of tests, and rubrics were built based on descriptions of the behavioral indicators and quality criteria of experimental competency as shown in Table 2
2.3 Findings
To answer the research question, we presented how to design the evaluation tool, proof collection, and data processing ways
Select assessing tools for students' experimental competence
With the expression of the experimental competency frame in Table 2, we can see the following results:
The 5th and 6th expressions are the implementation of the laboratory manipulation which can only develop when the students conduct experiments and assessments through teacher supervision (Obviously, can be observed directly or via video)
The remaining manifestations (1, 2, 3, 4, 7, 8, 9) are expressed in thinking, exchanging, presenting, or answering questions by saying and writing Teachers cannot assess the student's thoughts The oral presentation and answering the question that cannot appreciate all students, unless students write on paper as evidence Therefore, the issue here is the need to design learning slips or tests This means that the learning slips have to include the requirements for students to write down corresponding to the manifestations of the experimental competence Designing tests is similar to the worksheet and it is called a specific test (there are more special requirements than traditional tests that students only choose or write the answer, some contents that need not be written)
With such analyses, the tools are determined to develop and evaluate the students’ experimental competence as follows:
Trang 6No Evaluation tool Quality criteria Using Evidence
1 Worksheet and
rubric 1, 2, 3, 4, 7, 8, 9
experiments in teaching Chemistry with each student
Student's study slip
teaching on video
Students' actions that can be observed
3 Specific test (on
paper) 1, 2, 3, 4, 7, 8, 9
After teaching, for each student Test
Design assessing tools for students' experimental competence
2.3.1 Worksheet
In teaching chemistry, experiments are used in many different ways and purposes By using experiments to form new knowledge and skills for students is an effective way to develop students’ experimental competencies For this purpose, experiments are usually used according
to four methods, that is to use experiments: Follow the scientific method; To verify students’ new judgments; To create conflicting awareness, to solve problems; To illustrate new knowledge and skills In which the 4th method is the least aggressive so we do not choose to perform in this study According to the first method, there are 3 experimental worksheet examples below:
Instructions for using these worksheets in teaching are: Students in the classroom are divided into groups, about 6 members in a group The teacher assigns tasks, guides how to work (according to the worksheets) students working based on guidelines Students report results, discussions
Example 1 Worksheet 1
The worksheet when using experiments to verify the new judgment
Content: Chemical properties of Glucose (Glucose - Chemistry 12th grade, Vietnamese textbooks)
The content of the study slip and the corresponding manifestations can be assessed:
The study sheet is used for students to learn the chemical properties of Glucose (Glucose - Chemistry 12th grade, Vietnamese textbooks)
Below are the content and evaluation criteria of students' experimental capacity according
to the corresponding tasks in worksheet 1
WORKSHEET 1
(Chemical properties of Glucose)
Full name:……… Class:……
(1) Individual work
Make requests or answer the following questions:
- What functional groups are in glucose? Predict what is the
chemical reaction of glucose?
………
………
- From the chemicals and apparatus gave below:
+ Chemicals: glucose, CuSO4, NaOH, AgNO3, NH3 solutions
Manifestation 1, 2, 3,
4
1 Identify the purpose
of the experiment 2 Formulate scientific predictions/
hypotheses 3 Identify tools and chemicals needed
Trang 7+ Apparatus: Test tubes, wood clamps, alcohol lamp
Propose two experiments to verify the chemical properties of
glucose Describe procedure, predict phenomenon, and basis to
predict phenomenon (by writing chemical equations and describe
the state, color of products) in columns (1), (2), (3), and (4) of the
following table
(2) Team discussion and do experiment
Members share their answers, unify the procedure
(Using the different color pen to fix in the table (if do))
All the members do experiments in the way agreed above
Write the observing phenomena, explain and draw conclusions in
columns (5), (6)
4 Identify the steps for conducting the experiment’s
procedure
Expression 7, 8, 9
experimental data
8 Analyze experimental data
9 Draw scientific conclusions
Example 2: Worksheet 2
The worksheet when using experiments to follow the scientific method Content: The
chemical properties of Sucrose (Lesson: Disaccharide - Chemistry grade 12, Vietnamese textbook)
The content of the study slip and the corresponding manifestations can be assessed:
The study sheet is used for students to learn the chemical properties of sucrose (Disaccharide - Chemistry grade 12, Vietnamese textbook)
Below are the content and evaluation criteria of students' experimental capacity according
to the corresponding tasks in worksheet 2
WORKSHEET 2
(Chemical properties of sucrose) Name:………
Class:………
(1) Individual work
Make requests or answer the following questions:
- Predict and write the hydrolytic reactivity of sucrose in acidic medium
(reactivity, products, way to identify those products and phenomenon):
………
………
- From the chemicals and apparatus given below:
+ Chemicals: Sucrose, H2SO4, NaHCO3, AgNO3, NH3, NaOH, CuSO4
(solutions)
+ Apparatus: Test tubes, wood clamps, alcohol lamp
Propose one the experiment to research the hydrolysis of sucrose
Describe procedure, predict phenomenon, and basis to predict
phenomenon (by writing chemical equations and describe the state, color
of products) in columns (1), (2), and (3) of the following table
Manifestation
1, 2, 4
1 Identify the purpose of the experiment
2 Formulate scientific predictions/hy potheses
4 Identify the steps for conducting the experiments
Trang 8(2) Team discussion and do experiment:
Members share their answers, unify the procedure
(Using the different color pen to fix in the table (if do))
- All the members do an experiment to investigate the hydrolytic reaction
of saccharides according to the proposed experiment above
Write the phenomenon, explain, and conclude in columns (4), (5)
procedure
Expression 7,
8, 9
7 Collect experimental
Analyze experimental data 9 Draw scientific
conclusions
Example 3: Worksheet 3
The worksheet when use experiments to create cognitive conflicts and solve problems
Content: aromatic substitution reactions of aniline derivatives (Lesson: Aniline - Chemistry
grade 12, Vietnamese textbook)
The content of the study slip and the corresponding manifestations can be assessed:
The study sheet is used for students to learn the chemical properties of aniline (Aniline - Chemistry grade 12, Vietnamese textbook)
Below is the content and evaluation criteria of students' experimental capacity according to the corresponding tasks in worksheet 3
WORKSHEET 3
(Chemical properties of Aniline)
Name:……… Class:…………
Individual work and Team discussion
Predict phenomenon and explain the experiment in the
following table:
Procedure
Predict phenomenon (pre-experiment)
Basis to predict phenomenon Add a few drops
of bromine water
into a test tube
that already
contains 1 mL of
aniline
Manifestation 1, 2
- Identify the purpose of the experiment
- Formulate scientific
predictions/ hypotheses
Expression 7, 8, 9
- Collect experimental data
8 Analyze experimental data
9 Draw scientific conclusions
Trang 9Team discussion
a) Share your answers and conduct experiments according
to the instructions above, describing the observed
phenomenon
……… …………
b) Comparing observed phenomena when conducting
experiments with predictive phenomena, what
conclusions are drawn?
……… …………
c) Read the section on " aromatic substitution reactions of
aniline derivatives - Vietnamese textbook - page 43",
explain the observed phenomenon, conclude the
properties of aniline
………
2.3.2 Rubric
Table 2 The rubric of the students’ experimental competency
Use this rubric to evaluate students' experimental abilities when comparing students' study slip performance with the descriptions described in Table 2
School: Class: Group:
Name:
The experimental competency assessment criteria Mark
1 Identify the purpose of the experiment
2 Formulate scientific predictions/ hypotheses
3 Identify tools and chemicals needed
4 Identify the steps for conducting experiments
5 Make safety rules when doing experiments
6 Perform experimental manipulations
7 Collect experimental data
8 Analyze experimental data
9 Draw scientific conclusions
2.3.3 The specific test
Pre- and post-test tests are designed as exercises These include making predictions, proposing how to conduct experiments, predicting phenomena, performing experiments, describing phenomena and information gathered from experiments, and analyzing results to conclude With those tasks in the test, students also show the manifestations of experimental capacity similar to the learning cards
Below is an illustration of the test before and after the pedagogical experiment
Trang 10Example 1: Pre-test
PRE-TEST Time: 45 minutes Name:……… Class:………
In the laboratory, there are chemicals: Mg, Cu pieces, CuO powder, dilute NaOH solution, dilute CuSO4 solution, CH3COOH solution, CaCO3, purple litmus, phenolphthalein solution, HCl solution, and essential apparatus
Question 1: Choose chemicals above, propose apparatus and procedure steps to do an
experiment, prove the acidic property of acetic acid Describe in the following table:
Experiment Chemicals Apparatus Procedure Phenomenon Explanation
Acetic acid
reacts with
………
………
Question 2: Conduct experiments according to the proposal Compare the phenomenon before
and after experimenting, explain, and conclude about chemical reactions of acetic acid
Example 2: Post-test
POST- TEST
Time: 45 minutes
Name:……… Class:………….…
There are 3 colorless solutions: Glucose, sucrose, ethanol which are contained in the vials without a label
Question 1: Perform a diagram showing how to identify 3 solutions Propose apparatus,
chemicals and describe procedures to do experiments (by words or pictures with notes) according to the diagram above
Experiment Apparatus Chemicals Procedure, phenomena (prediction)
Question 2: Conduct experiments according to the proposal Record the phenomena different
from the original prediction (if any), explain and conclude the name of each solution in each test tube
From answering question 1 in the test questions, teachers can evaluate behavioral indicators 1, 2, 3, 4 The implementation and answer of question 2 will evaluate the behavioral indicators 5, 6, 7, 8, 9 Based on the answers on the test and observing the experimental manipulations of students (direct observation or video recording), teachers follow the description in Table 2 to evaluate the score of each criterion
In these tests, if not performed in the laboratory, it may be replaced by a request to conduct the test through some pictures of the experimental phenomenon of acetic acid with substances From there, ask students to observe, compare and draw conclusions However, criteria 5 and 6
cannot be assessed
2.4 Analyzing and discussing
During experiments, students do in a group so that it cannot be judged by criteria 5, 6 of all students, this article only handles the scores of manifestations 1, 2, 3, 4, 7, 8, 9