Activity 1 - What is the purpose of practical work?
In this activity delegates think about a range of practical activities using a
selection of practicals taken from typical KS3 and KS4, or KS1 and KS2
schemes of work.
These are illustrated by brief instruction sheets (below). Each instruction
sheet provides a web link where full information can be found.
Working individually, each delegate attaches a label (e.g. a ‘Post-It’ note) to
each practical to identify the key purpose or objective of the activity.
Working in small groups of three or four people, the labels are then classified
under headings chosen by the group.
Note: If you are carrying out mixed primary-secondary CPD sessions you may
find it helpful to print out the primary and secondary practicals on different
colour paper.
What is the purpose of this
practical activity?
List of secondary practicals
1.
Testing a leaf for starch
13. Looking at a heart
2.
How much energy is there in food?
14. Effect of size on uptake by diffusion
3.
Preserving food
15. Measuring reaction time of a human reflex action
4.
The causes of rusting
16. Preparing a soluble salt by neutralisation
5.
Melting and freezing stearic acid
17. Alkali metals
6.
Change in mass when magnesium burns
18. Identifying the products of electrolysis
7.
Law of reflection
19. Ticker-timers for investigating speed
8.
Using ammeters
20. Simple electromagnet
9.
Experiments with magnets
21. Student power
10. Reaction between carbon dioxide and water
22. Earthquakes in the laboratory
11. The Moon's distance from Earth
23. Water expands when it freezes
12. Chemicals from seawater
24. Extracting metals with charcoal
List of primary practicals
1.
Make friends with a tree
11. In control
2.
Peace at last
12. Colour mixing
3.
A light for
13. Look around you
4.
Making Sandcastles
14. Slugs
5.
Curtains
15. Investigating ice
6.
Can colours compete with the sun
16. Kites
7.
Bone mystery
17. Classroom percussion
8.
Design a seed
18. Magic or magnetic
9.
Paper towel magic
19. Moss mat
10. Bishops can fly
20. Paper planes
Testing a leaf for starch
This procedure kills a leaf, disrupts the cell membranes and softens the cuticle and cell walls.
This makes it possible to extract the chlorophyll with hot ethanol and also allows the iodine
solution to penetrate the cells and react with any starch present.
http://www.practicalbiology.org/areas/introductory/energy/photosynthesis/testing-leaves-forstarch-the-technique,73,EXP.html
How much energy is there in food?
Take samples of a range of foodstuffs and set them alight in turn. Burn food samples under a boiling
tube containing a measured amount of water. Measure the temperature increase in the water.
Calculate the amount of energy needed to cause that temperature increase. This gives an estimate
of the amount of energy stored in the food. The apparatus is very simple and the protocol gives only
a very approximate estimate for each foodstuff, so there is scope for students to suggest
improvements in an evaluation.
http://www.practicalbiology.org/areas/introductory/energy/energy-in-food/how-much-energy-is-there-infood,42,EXP.html
Preserving food
Pupils investigate the effect of different preservatives on frozen peas in order to establish
that decay is caused by the action of microbes, and therefore preservatives work by reducing
microbe activity.
http://www.practicalbiology.org/areas/introductory/health-and-disease/preserving-food/preservingfood,96,EXP.html
Law of reflection
Class experiment showing that angle of incidence is equal to angle of reflection.
http://www.practicalphysics.org/go/Experiment_644.html?topic_id=2&collection_id=101
Using ammeters
In this experiment pupils measure the current at various places in series and parallel circuits.
This provides an opportunity to introduce the ampere unit.
http://www.practicalphysics.org/go/Experiment_271.html?topic_id=8&collection_id=32
Experiments with magnets
Magnets provide an introduction to attraction and repulsion, and to action at a distance.
Pupils investigate pairs of magnets, plotting compasses and iron filings.
http://www.practicalphysics.org/go/Experiment_189.html?topic_id=3&collection_id=26
The Moon’s distance from Earth
An estimate of the ratio of the Moon’s distance from the Earth compared to its diameter. To
complete this experiment, hold a small coin just beyond arm's length and adjust its distance
from the eye until the disc of the coin just obscures the disc of the moon. A partner can then
measure the distance from the eye to the coin.
http://www.practicalphysics.org/go/Experiment_936.html?topic_id=43&collection_id=115
Investigating the effect of caffeine on the
reaction time of a human reflex action
Pupils use a familiar protocol (dropping and catching a metre ruler) to investigate the effect
of drinking caffeinated drinks on their reaction times.
http://www.practicalbiology.org/areas/intermediate/control-and-communication/reflex-actions/measuringreaction-time-of-a-human-reflex-action,88,EXP.html
Ticker-timers for investigating speed
Making ticker-timer charts can develop an understanding of speed-time graphs.
One person should operate the ticker-timer switch while another walks away, pulling tape
through the ticker-timer. The walker should speed up and then slow down and stop, while
the tape is running through the timer.
http://www.practicalphysics.org/go/Experiment_266.html?topic_id=3&collection_id=31
Simple electromagnet
An introductory experiment using a wire wrapped round an iron nail, which shows that
electromagnets can conveniently be switched on and off.
http://www.practicalphysics.org/go/Experiment_323.html?topic_id=7&collection_id=43
Student power
Students measure their personal power by running up a flight of stairs.
http://www.practicalphysics.org/go/Experiment_511.html?topic_id=39&collection_id=74
Water expands when it freezes
In this demonstration a bottle is filled with water and allowed to freeze. The water expands
as it freezes which breaks the bottle. This is useful when teaching about the weathering of
rocks and freeze-thaw.
http://www.practicalchemistry.org/experiments/introductory/the-earth/water-expands-when-itfreezes,190,EX.html