Activity 2
Coffee
W
hen was the world’s favourite drink first
discovered? About a thousand-years-ago by an
observant Ethiopian goat-herd, who wondered
why his goats became livelier after eating berries from a
certain plant. In this activity, students learn about coffee’s
Book Reference: discovery before devising and doing an investigation to test the
Coffee, page 12. hypothesis “does caffeine increase alertness, and if so, by how
much?”
Curriculum link
11-14 QCA 9b – fit and healthy
• What effects do drugs have on how the body works,
physically and mentally?
Scientific enquiry
• Consider factors to take into account when collecting
evidence
• Decide the range of data to collect and technique to use
• Make enough measurements to obtain reliable evidence
• Use measurements to support a prediction
• Suggest improvements to the method used
Learning objectives
Students will learn:
• How an Ethiopian Arab – Khalid – discovered coffee more than 1000
years ago
• To devise and do an investigation to test the hypothesis that caffeine
increases alertness
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Activity 2
Running the activity
Starting the activity Distance Reaction
Display Activity 2a (either projected or as an OHT). Ask small groups of the ruler time/
students to discuss these questions: How do you like your coffee? How do falls be- millisec-
caffeine drinks make you feel? Then get students to guess when and where fore it is onds
coffee was first discovered. caught/
cm
Running the main part of the activity
5 107
Display Activity 2b, and take students through the story of how Khalid
discovered the stimulant properties of coffee. Emphasise the scientific skills 6 108
he used: careful observation; wondering why; devising an investigation to 7 114
find out more.
8 121
Then give each group copies of Activity 2c and 2d, which set the main
investigation task and give an outline to guide students through the 9 128
process. A failsafe alertness test is to get one student to drop a metre ruler 10 135
and another to catch it. Use the data in the table on the right to calculate
11 142
reaction times.
12 149
Some groups may well need help with considering how to make their
investigation fair and reliable, and with working out what data to collect for 13 156
strong evidence. 14 163
Once students have completed their plans, ask them to carry out their 15 170
investigation. Each group will need:
16 177
• A metre ruler
17 184
• Caffeine drinks (cola is a good alternative to coffee, as it can be served
cold!) 18 191
• Clean cups
• Clean measuring jugs/cylinders – perhaps borrowed from food
technology Current research suggests
Running the plenary that caffeine definitely
helps to keep you awake
Discuss students’ investigation results and evaluations, and come to a class and that it also may
conclusion about whether caffeine increases alertness. increase your reaction
time. However, it probably
Web links hinders performance on
complex analytical tasks.
http://www.ase.org.uk/htm/teacher_zone/upd8/upd8_26/upd8_wired.php Caffeine also speeds up
the heart and raises blood
This Red Hot Science activity on the ASE website gives further details pressure, so interfering
about ways of investigating other effects of caffeine, such as concentration, with sleeping. It can also
mood, memory and coordination. be addictive.
http://muslimheritage.com/topics/default.cfm?ArticleID=378
More information on the history of coffee.
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Activity 2a
1
Activity 2b
1
Activity 2c
1
Activity 2d
1