CHAPTER 9
TIME AND TEMPERATURE
As often happens in the UK we have two systems for both time and temperature, where really one would do.
Time
Actually, when we look at time it is more complex than it looks, and can be very confusing to ESOL learners. Most cultures use both the analogue and digital systems for telling time, but not all cultures and countries use the 12 and 24 hour clock systems, preferring to stick to the 24 hour clock to avoid confusion. Spanish students are, among others, perplexed by the 12 hour clock.
In addition not all languages use the same ways of describing the time in relation to the hours, for instance in French the literal translation for 7.45 is not a quarter to eight, but eight less a quarter, and in German it is a quarter before eight. Confusingly in German 8.30 is ‘halb neun’, or half (to) nine, which is fine, except in English we would say half eight, having dropped the ‘past’ out of ‘half past eight’.
In the UK we seem to say the time differently if reading from analogue as opposed to digital clocks, for instance 2.55 is fine if we are reading from a digital watch, but if using an analogue watch face we are much more likely to say ‘five to three’. ESOL learners will need to be taught both systems, and this topic will come up in ordinary ESOL lessons as well as ESOL maths.
Temperature
Temperature also uses two systems, namely Celsius, also known as Centigrade, and Fahrenheit. Celsius is a Swedish system which has been used increasingly in the UK over the last 40 years or so and is easy to remember because it is based on the boiling and freezing points of water. Water boils at 100*C and freezes at 0*C. In the Fahrenheit system, which was invented at a very similar time to Celsius, around 1700, but in Germany, water freezes at 32*F and boils at 212*F.
Many of the older generation in the UK still use the Fahrenheit system, and it is a popular topic on exam papers for conversions, and comes in at Level 2 of the FS maths curriculum. A formula will always be given for these conversions, but using it effectively does require knowledge of BODMAS, which is the order that Maths calculations must be done in, unless you are told otherwise.
B stands for brackets (like this)
O stands for operation, such as when we square or cube a number, such as r squared.
D stands for division
M stands for multiply
A is addition
S is for subtraction
Thus using BODMAS 27 + 0.4 x 3 would be 0.4 x 3 = 1.2, then add 27 = 28.2
If I don’t use BODMAS I would get 27.4 x 3 = 82.2; this is the wrong answer and it is very different, though in this case interestingly the numbers are transposed, i.e. the 2 and the 8 have swapped position.
Some students may know BIDMAS, where the I stands for indices.
A formula for the conversion of temperature may look like this: C = ( F – 32 )5/9.
ESOL learners may have their own version of BODMAS using their first language, and it could be worth displaying all the different versions on a poster in the classroom, firstly as a memory aid, but also to show that maths skills in the first languages are acknowledged and valued.
JMS 2013/14