Program Organization

Facilities and Materials

Facilities and materials, by themselves, do not create a science course. They are essential, but proper use of the facilities and materials with students is critical. Since a wide range of teaching strategies is desirable in this course, more flexible teaching areas are useful. This might be a well designed laboratory which can be reconfigured to accommodate small group discussions, small group and large group laboratory activities, lectures, research, or other activities. Or, it may be a combination of two or more existing rooms.

Below are some features of a good science laboratory/facility.

Two exits, remote from each other.
Master shut-off controls for the water, natural gas, and electrical systems. These should be easily accessible and easy to operate.
Spacious activity area where students can work without being crowded or jostle.
Safety equipment that is visible and accessible to all.
Ventilation system which maintains negative pressure in the lab.
Enough electrical outlets to make the use of extension cords unnecessary. The plugs should be on a ground fault interruptor system or individually protected.
Emergency lighting.
Separate, locked storage rooms and preparation rooms to which students' access is restricted.
Adequate shelving so that materials do not have to be stacked, unless it is appropriate to store them that way.
Separate chemical storage cabinet with provisions for proper storage of all classes of chemicals.
Audiovisual storage area for charts, video and audio tapes, slides, and journals.
Areas for plant and animal care.
Storage area for student assignments.

Science equipment and supplies are valuable resources. Not only are they becoming more expensive, but they are also indispensable to the proper presentation of science. There are several reasons for having an efficiently operating inventory system. Such a system can prevent running short of a consumable supply, prevent ordering something already in adequate supply, and save time when ordering. It can act as a quick reference to determine whether a particular item is available. It may also be useful for insurance purposes.

In addition to inventory control, maintenance and storage are important considerations. A regular procedure for maintenance ensures that the equipment is ready for use when it is needed and is in safe operating condition. Adequate storage space ensures that the equipment can be preserved in good condition and that it is safely away from unauthorized use. It also helps convey the message that laboratory equipment and supplies are not toys, and that a lab is not a place to play with equipment.

Safety

Safety in the classroom is of paramount importance. Other components of education - resources, teaching strategies, facilities - attain their maximum utility only in a safe classroom. Safety is no longer simply a matter of common sense. To create a safe classroom requires that a teacher be informed, be aware, and be proactive. There are several ways the teacher can become in- formed. Check these reading materials.

Safety in the Secondary Science Classroom. (1978). National Science Teachers Association, 1742 Connecticut Avenue North West, Washington, D.C. 20009.
A Guide to Laboratory Safety and Chemical Management in School Science Study Activities. (Saskatchewan Environment and Public Safety, revised, 1992).

Safety sessions are often offered at science teachers' conventions. Many articles in science teachers' journals provide helpful hints on safety. Professional exchange may provide teachers with an outside viewpoint on safety.

Awareness is not something that can be learned as much as it is developed through a visible safety emphasis: safety equipment such as a fire extinguisher, a fire blanket, and an eye wash station prominently displayed; safety posters on the wall; a "safety class" with students at the start of the year; and regular emphasis on safety precautions while preparing students for activities.

Proaction is accomplished by acting on what is known and by being vigilant. Six basic principles guide the creation and maintenance of a safe classroom.

Model safe procedures at all times.
Instruct students about safe procedures at every opportunity. Stress remembering to use safe procedures when experimenting at home.
Close supervision of students at all times during activities, along with good organization, can avert situations where accidents and incidents can occur. Inappropriate behaviours in a classroom, and more particularly in a laboratory, can result in physical danger to all present and destroy the learning atmosphere for the class.
Be aware of any health or allergy problems that students may have.
Display commercial, teacher-made, or student-made safety posters.
Take a first aid course. If an injury is beyond your level of competence to treat, wait until medical help arrives.

To compile a complete list of safety tips is impossible. This list might be termed a "highlight" list. It does not cover all situations and events which might occur in a classroom. It is the responsibility of each teacher to be functioning at the highest level with respect to creating a safe classroom climate.

Check your classroom for hazards on a regular basis.
Create a bulletin board with a safety theme.
Make a rule that all accidents must be reported to the teacher.
In case of a serious accident, pick one person who is present and send that person for expert, professional, or additional help. Then, take action. Remember, you are in charge of the situation.
Become familiar with the school division's accident policy.
Do not give medical advice.
Move an injured person as little as possible until the injury assessment is complete.
Emphasize that extra caution is needed when using open flames in the classroom.
Require the use of goggles when using open flames, corrosive chemicals, or other identifiable hazards.
In case of fire, your first responsibility is to get students out of the area. Send a specific person to give an appropriate alarm. Then assess the situation and act.
Avoid overloading shelves and window sills.
Properly label all containers of solids, liquids, and solutions.
Separate broken glass from other waste.
Advise students not to touch, taste, or smell chemicals unless instructed to do so.
Each laboratory should have one first aid kit which is not accessible to students, but is only for the teacher's or administrator's use.
Master shut-off controls for gas, electricity, and water should be tested periodically to ensure that they are operable.
Safety equipment such as fire extinguishers, fire blankets, eye wash stations, goggles, fume hoods, test tube spurt caps, and explosion shields must be kept in good order and checked regularly.
Electrical cords must be kept in good condition, and removed from outlets by grasping the plug.
Students should use safety equipment - protective eye wear, protective aprons or coats, fume hoods, etc. - whenever practical and necessary.
Students should tie back long hair and refrain from wearing loose and floppy clothing in the laboratory.
Students should not taste any materials, eat, drink, or chew gum in a laboratory.
Students should follow recommended procedures and check with teachers before deviating from such procedures.
Students should be required to return laboratory equipment to its proper place.
Chemicals or solutions should never be returned to stock bottles.
Pipetting should be done only with a safety bulb, never by mouth.
Acids or oxidizers should never be mixed with compounds containing chlorine (e.g., bleach).
Mercury thermometers should be replaced with alcohol thermometers.
Asbestos centred wire mats should be replaced with plain wire mats or with ceramic centred mats.
The use of human biological fluids in laboratory activities should be closely monitored.
- Students should use only materials from their own body - saliva, epithelial cells - when doing lab activities requiring those materials.
- Students should have no contact with bodily fluids from another student.
- Alcohol prep pads should not be used more than once.
- Students should wash their hands thoroughly with soap and water after handling any bodily fluids.
Specimens for dissection, dissecting tools and equipment, and chemicals used in biology must be kept under locked storage.
When field materials such as pond or slough water, plants, soil, or insects are collected, assume that they are contaminated by pathogens and treat them as such.
Known pathogens should not be cultured. Exposure plates and culture plates with unknown bacterial colonies must be treated as though they are contaminated by pathogens until it can be shown otherwise.
Make sure that autoclaves are in good operating condition.
Adequate ventilation is essential when working with specimens preserved in formalin or formaldehyde.
Proper care must be given to animals kept in a classroom. Refer to a good animal care book, if needed.
Use rubber gloves and take great care when handling any plant growth hormones such as colchicine, gibberellic acid, indole acetic acid, or Rootone(TM).
Many plants may contain toxins or allergens. Students should be cautioned not to taste or handle plants. Teachers are responsible for familiarizing themselves with any local, provincial, or federal legislation pertaining to plants and animals. If in doubt, inquire.
Chemicals should be stored in a locked area, to which access is restricted.
Be prepared to handle all chemical spills rapidly and effectively.
Inspect glassware (e.g., beakers, flasks) for cracks and chips before using them to heat liquids or hold concentrated corrosive liquids or solutions.
Chemical storage should be organized by groups of compatible compounds, rather than by alphabetical order. (Within a group of compatible compounds, alphabetizing can be used.)
Electrical equipment (e.g., transformers, induction coils, electrostatic generators, oscilloscopes, discharge tubes, Crookes tubes, magnetic effects tubes, lasers, fluorescent effects tubes and ultraviolet light sources) must be kept in locked storage.
Discharge tubes can produce x-rays which may penetrate the glass of the tube if operating voltages higher than 10 000 volts are used.
Lasers are capable of causing eye damage. The lens of the eye may increase the intensity of light by 1 000 000 times at the retina compared to the pupil. To reduce risk, lasers rated at a maximum power of 0.5 mW should be used.
- Lasers should be used in normal light conditions so pupils are not dilated.
- Everyone should stay clear of the primary and reflected paths.
- Everyone should be alert to unintended reflections.
Contact lenses complicate eye safety. Dust and chemicals may become trapped behind a lens. Gases and vapours may cause excessive watering of the eyes and enter the soft material of the lens. Chemical splashes may be more injurious due to the inability to remove the lens rapidly and administer first aid. The loss or dislodging of a contact lens may cause a safety problem if it happens at a crucial moment.
On the other hand, contacts, in combination with safety eye wear, are as safe as eyeglasses in most cases. Contacts may prevent some irritants from reaching the cornea, thus giving the eye some measure of protection. The Saskatchewan Association of Optometrists feels that, as long as proper, vented safety goggles are worn, there is no greater risk in a lab situation for a person wearing contacts than for one not wearing contacts. The Association recommends that:
- teachers know which students wear contact lenses;
- teachers know how to remove contact lenses from students' eyes should the need occur;
- there be access to adequate areas for the removal and maintenance of contact lenses; and,
- contact lens wearers have a pair of eye glasses to use in case the contact lenses must be removed.

Disposing of Chemicals

Some precautions should be followed when disposing of chemicals.

A Guide to Laboratory Safety and Chemical Management in School Science Study Activities categorizes all chemicals by disposal category. Disposal of liquid or aqueous wastes from categories 1 and 2 should involve dilution before pouring them down the drain, then running tap water down the drain to further dilute their strength.
Solid wastes should be rinsed thoroughly with water. They should be disposed of in a specially marked waste container - not the general class waste basket. The janitor should be alerted to the existence of this container and be assured that none of the materials are hazardous.

If, for any reason, substitutions are made for materials, it is the responsibility of the teacher to research the toxicity, potential hazards, and the appropriate disposal of these substituted materials.

Federal, provincial, and municipal regulations regarding the labelling, storage, and disposal of hazardous substances should be followed. Under current Workplace Hazardous Materials Information System (WHMIS) regulations, all employees involved in handling hazardous substances must receive training by their employer. For more information, contact the Canadian Centre for Occupational Health and Safety, or Saskatchewan Human Resources, Labour and Employment.

A Broader Look at Safety

Normally, safety is understood to be concerned with the physical safety and welfare of persons, and to a lesser degree with personal property. The definition of safety can also be extended to a consideration of the well-being of the biosphere. The components of the biosphere Ä plants, animals, earth, air and water - deserve the care and concern which we can offer. From knowing whether wild flowers can be picked to considering the disposal of toxic wastes from Middle Level science rooms, the safety of our world and our future depends on our actions and teaching in science classes.

The Workplace Hazardous Materials Information System (WHMIS) under the Hazardous Products Act governs storage and handling practices of chemicals in school laboratories. All school divisions should be complying with the provisions of the Act.

Measurement

An understanding of the importance of measurement in science is critical for each student to acquire. The importance of measurement can be seen when it is viewed as one component of the Common Essential Learning of Numeracy. There is an implicit assumption in science, and in society, that quantitative statements are more authoritative than are qualitative statements. Yet, many important advances in science are made through intuition and through creative leaps. Advances in science are not restricted to data analysis. Students must see that measurement is important, but important in its context.

To make quantitative statements, measurements must be made. The accuracy of the measurements determines the confidence placed in the facts which are derived from the measurements. If the facts are represented as being accurate, the measurements must be equally accurate. But accuracy is not the only factor to consider when measurement is discussed.

The ability to make measurements depends on the technology available. A metre stick can be used to measure the length of a table. What technology is available to measure the diameter of an atom? Such measurements require a greater degree of faith in the technology. At the furthest reaches of scientific inquiry, technology must be devised so that the results of exotic experiments can be detected, measured, and interpreted. What is measured depends upon the assumptions made in the design, and on the limitations of the technology.

The ability to make measurements depends on the correct use of the technology. Proper procedures must be followed, even with the use of simple devices such as thermometers, if measurements which accurately represent the system under observation are to be made. In addition to proper procedures, the measurement devices must be used appropriately. Even though a thermometer has a ruled scale, to measure the length of a pencil in degrees Celsius is not a useful way to represent length.

There must be as little interaction as possible between the technology, or application of it, and the object being measured. If the device used to measure the temperature of a system changes the temperature of that system by a significant amount, how useful is the measurement? Heisenberg faced a similar problem in attempting to determine the momentum and the position of the electron in the atom. Precision in determining one results in less information about the other.

Before the matter of accuracy is addressed, the student must have an understanding of what technology is available, its appropriateness for the situation, the proper use of that techno- logy, and the limits which are inherent in the technology. Once that is understood, the student can then manipulate the technology to give the most accurate and precise results.

One aspect of accuracy pertains to the matter of uncertainty in measurement. The percentage error in a measurement, or the absolute error, is a concept students must consider. No measuring instrument has zero margin of error. No operator is capable of using an instrument so that no measurement error is introduced. Measurement error exists and must be accounted for in recording and interpreting data. A particular balance may have an uncertainty of measurement of 0.01 g, for example, if the balance is levelled, properly adjusted, and working well. This balance has a suitable accuracy for measuring a mass of 142.87 g but not for measuring a mass of 0.03 g. Calculate the percentage error in each case and the point is clear. However, the 0.007% measuring error for the 142.87 g mass which is due to the balance may be made entirely insignificant by operator errors such as having the balance pan on the wrong hook, misreading the scale, not zeroing the balance before starting, stopping the oscillation of the beam with a finger, using a wet or dirty pan, and so on. Accuracy requires both good technology and good technique.

Another concern is that of significant figures. Measuring instruments can only supply a limited degree of accuracy. The problem most often encountered with students is to have them make use of the maximum precision possible, without having them overstate their case. If seven identical marbles have a total mass of 4.23 g, the average mass of a marble is not 0.604 285 714 g. A more reasonable report would express the average mass rounded off to two decimal places.

Many science texts have sections dealing with the reporting of uncertainty in measurement and significant figures. Each teacher should find an approach that is comfortable for both the teacher and the students and then adopt and emphasize that approach.

Data analysis is an important related topic. Often, in order to make sense of measurements, data must be organized and interpreted. Students must learn to organize their data collection and recording so that it is ready for analysis. Graphical analysis is often useful and should be stressed. The use of computer software is also an option for recording and analysis. Databases can be used to store and then manipulate large amounts of data. Spreadsheets are also useful for organizing data. Many database and spreadsheet programs, as well as integrated software packages, contain graphing utilities and may contain statistical analysis options. Graphing and statistical analysis packages may also be purchased as stand-alone software. The use of computer analysis should be encouraged wherever possible.

In addition to the use of computer analysis, hardware interfaces to allow the input of data through sensors, which the software then interprets as measurements, are a valuable addition to a science lab. It should be emphasized that the use of a computer does not mean that the results will be error free. Accuracy is mainly a function of the technician and, to a lesser degree, of the technology.

Measurements should be expressed using SI units, or SI acceptable units, whenever this is realistic or feasible to do so. Common non-metric units may be used if necessary. Conversion factors from non-SI to SI or within the non-SI units may be necessary. Each teacher should follow the recommendations of the Canadian Metric Commission with respect to the basic and derived units of measurement and the proper symbols for those units.

If detailed information is required, refer to the Canadian Metric Practice Guide (CAN3-Z234.1-79 from the Canadian Standards Association, 178 Rexdale Boulevard, Rexdale, Ontario M9W 1R3), the International System of Units (SI) (CAN3-Z234.2-76 from the CSA) or the SI Metric Guide for Science (Saskatchewan Education, 1978).

During grade 9, scientific notation should be used so that students become familiar with reading, manipulating, and writing numbers in that format. In addition to the value of SI-notation for ease in handling very large or very small numbers, students must be able to use this notation to express the number of significant figures in a large number, and to perform calculations using scientific notation.

Plant and Animal Care in the Classroom

Teachers are responsible for familiarizing themselves with any local, provincial, or federal statutes pertaining to the care of plants or animals. If in doubt, inquire. Pet shops or plant shops may have useful information. There are regulations preventing the picking of wild flowers, or the captive use of migratory birds or endangered species.

Involve students in helping to care for plants and animals; set up a daily schedule of things that have to be done. Rotating student responsibilities will involve more students. They should be able to discuss the kinds of things that plants and animals need to live and stay healthy. They can use these ideas to learn more about the plants and animals they are caring for.

Wear gloves when handling animals in the classroom. Overhandling can put the animals under excessive stress. Be wary of possible diseases that may be spread by the animals, or by people to the animals.

Inquire about specific feeding requirements for any classroom pets. Find out about the size of cage the animal needs, the type of nutritional requirements it has, whether or not it needs a separate container for water, and so on. Odour and lack of cleanliness will occur if animals are not maintained properly. Before you obtain an animal as a classroom pet, find out how much time and effort will be needed to care for it. Be prepared to make the necessary commitment if you have a pet in the classroom. Does the animal need a metal cage? Does it need an exercise wheel? Can it be stored in cardboard boxes, and if so, how often do the boxes have to be changed? These are the areas of concern when deciding on a type of pet to have in the classroom.

Poisonous animals, or other potentially dangerous animals such as venomous snakes and spiders should not be kept in the classroom.

The use of animals for purposes of experimentation has come under very close scrutiny in recent years. If an experiment can be performed in some other way than by using live or preserved specimens, then do so. Alternatives might include computer simulations and research projects.

Some people may have allergies to certain plants and animals. Be wary of any possible signs of allergic reactions among students. Some plants are toxic and should not be used in the classroom. If in doubt, check about the plant first, and keep it out of reach of children until you are sure that it is safe.

Keep plants fairly far apart, so that if mites infest one plant they will not spread to other plants.

Plants and animals have certain environmental conditions which must be maintained to ensure their welfare. Room temperature, exposure to sunlight, humidity, noise, dust, and other such factors may have an effect on them.

Make arrangements to have the plants and animals looked after on weekends and over holidays.

Aquaria in the Classroom

The following suggestions may be helpful in setting up aquaria.

A glass container of any size can be used, from a large, well washed pickle jar to a 2 metre long tank.
Rinse any container several times before it is used.
Plan an appropriate environment for the fish.
Use clean, aerated water at an appropriate temperature (21 oC to 27 oC)
A source of diffused light over the tank is useful. Use full spectrum lighting if plants are growing in an aquarium.
Bottom gravel, water plants, and hiding places enhance the environment.
Plants can rarely supply enough oxygen for the fish.
Treated tap water must be left 48 - 72 hours in an open container, so that the chlorine in the water diffuses into the air. Adjust water temperature before adding fish.
When replacing water lost by evaporation, use water that has lost its chlorine and reached aquarium temperature.
A lid prevents excessive evaporation losses.
Indirect light, from a light in a lid or from the classroom, is better than direct sunlight.
Get help from your supplier to select fish based on several factors: hardiness, compatibility, available space.
Too few fish is better than too many.
Select a proper food and feed the proper amounts. Children will tend to overfeed the fish, causing a food decaying problem, if allowed to feed the fish whenever they wish.
Remove or treat diseased fish immediately.
Teach the children to avoid activities which put additional stress on the fish, such as tapping on the walls of the aquarium, poking the fish with pencils, or dropping paper or chemicals into the water.

Reference books are available at pet stores and in libraries. Some databases which can be accessed by computers also have area reserved for hobbyists.

Terraria in the Classroom

A terrarium simulates a natural land environment.

Use a large glass container - a pickle jar, fish bowl or aquarium.
Place the soil in layers: rocks or pebbles covered by activated charcoal, covered by topsoil.
Topsoil is a mixture of peat moss, potting soil, and sand, with proportions varying according to the environment you wish to create.
Activated charcoal chips, available at stores with aquarium supplies, absorb decaying organic material from the soil and water.
Completely moisten the soil before transplanting into it.
Use a loose fitting lid for a moist environment terrarium (with mosses, ferns, etc.). No lid is necessary for a dry environment (cactus) system.
Place moist environment terraria in indirect, but adequate, light. Dry environment terraria may be placed in direct sunlight.
Use occasional misting to maintain the humidity level.
If animals are added, you should ensure that they are not able to escape the terrarium and become a classroom nuisance.
Reference books on starting a terrarium may be found in the library.

Organizing a Field Trip

Field trips can and should be valuable learning experiences which allow students to apply their classroom learnings to an actual or "real" situation. Field trips also allow students the opportunity to learn directly rather than indirectly. Learning is enhanced through direct experience. Field trips are fun for everyone involved!

The key to successful field trip experiences is careful and thorough planning. This planning takes time and patience. Make sure to check to see if the school division has any special policies regarding field trips.

The simplest approach when planning a field trip is to treat the experience like the writing of a newspaper article, using the five Ws and How!

Why do you want to take your class on this particular trip?

Is this mainly a science activity or does it integrate activities in other subjects as well?
Are the planned activities valid learning experiences?

What learnings do you expect your students to gain from and apply to this experience?

Have objectives for the field trip been established?
Have appropriate activities and instructional approaches been selected?
Have you and your students done your background research?
Are expectations about student behaviour on the trip clear and realistic?

Where do you plan to go with your class?

Is it accessible to all students?
Is permission of landowners or officials required in order to visit this site?
Does the site have facilities such as bathrooms, lunch areas, shelters, appropriate emergency facilities, etc.?
Is it possible for you to visit the site beforehand?
Are locations established at which various activities will occur?

When do you plan to take this field trip?

Is there adequate time to plan the trip?
Will relevant information be provided to students before the field trip?
Is there adequate time after the field trip to do a wrap-up?
Are there any potential conflicts with the selected date?
Does the selected date indicate the need for special clothing or supplies?
Is there a contingency plan in case of bad weather?
Has parental consent been obtained?

How are you going to get to the site?

Will transportation be required?
Is appropriate transportation available and affordable?
Can the students be learning during the trip to the site?

How long will this particular trip be?

Can time be used efficiently and effectively?
Is there too much to do and too little time?
How does the field trip affect the rest of the school?
Will someone else have to do additional supervision duties?
Will others have to change their planned activities?
Will a substitute teacher be required?

Who is coming with you on the field trip?

Are there sufficient supervisors for the number of students involved?
Have the people in your community been utilized for their expertise?
Has the class been divided into working groups?
Have leaders responsible for coordinating the groups' activities been selected for the working groups?

Although this may seem like a great deal of work, planning should be done before embarking on a field trip. The more concrete and detailed the planning is, the more likely it is that the trip will be a success.

Once the groundwork has been set and administrative approval has been obtained, approach the parents and the students about the trip. It is advisable to send a letter home to the parents which details the proposed field trip. Include information on such things as the times of departure and return, the location of the field trip, the people responsible for supervision, clothing requirements, lunch plans, required materials, anticipated costs, and contingency plans. This letter could also include a request for parental help and a separate permission slip to be returned to the teacher. It is a good idea to have the letter signed by both the teacher and the principal before sending it to parents.

The parental consent form which follows serves as an example of one that could be used. Note that the use of a consent form does not remove the teacher or the school division from the possibility of incurring liability during the trip.

Sample Permission Form for Field Trips

Date:

Dear Parent/Guardian:

As a part of the school science program, we will be going on a field trip to _______________________. This field trip will provide your child with the opportunity to experience the following: (provide a brief list of the activities you have planned).

An itinerary and a schedule of our proposed activities during the field trip is included for your information. Please review this material and contact the school if you have any questions about our plans.

Your child should bring the following supplies on the field trip:________________________________ (list any special needs) ________________________________. If your child has any special physical or medical problems (e.g., allergies), please bring this to our attention. Contact the school if you feel that these problems may interfere with your child's participation in this activity.

We would like you to come along on this exciting learning experi- ence. We encourage you to sign up as a volunteer. Thank you for your cooperation.

_____________________
Teacher

_____________________
Principal

Consent Form

I will be able to take part in this field trip as volunteer.

Yes ______ No ______

Comments: ___________________________________________

I permit my child to take part in the field trip described above. I have notified the school of any physical or medical problems which might interfere with my child's participation in this activity.

Date:

Signature: