School Science Review, March 2006, 87(320) 69 Data-loggers in ecological enquiry in school gr ounds and beyond Frank Fearn Ideas and hints on using data-loggers to enhance outdoor enquiries ABSTRACT Most schools usedata-loggers in science, often to take readings in laboratory experiments. The use of data-loggers outside can improve the variety and rigour in ecological enquiry in school grounds. Four case studies illustrating outdoor enquiry-based applications, suitable for pupils aged 11–16, are presented: Pond enquiry; Mammal activity enquiry; Microenvironments in log piles and compost bins; Sphere of influence of trees. Hints and tips for successfuloutdoor data-logging are listed. Nearly 15 years ago I heard of a new product being developed by theequipment supplier , Philip Harris, which wouldcollect data, store them anddownload to a computer. At the time, my science department was rapidly increasing the use ofgraphing programs to display and analysedata, but teachers were becoming concerned at the amount of time pupils were spending inputting results. The new data- logger seemed to be an ideal tool toovercome this problem. As things turned out, we must have been one of the very first orders received by Philip Harris because they sent not onedata-logger , but eight, on the understanding that we would ‘road-test them’ and present our findings both to the Association for Science Education (as a display at the Annual Meeting) and to the Design Council (as a video). I quickly found that some of the most interesting uses of this new tool were outside in the field. Our school had a tradition,each June, of taking a group of about 25 year 7 pupils (11/12 year-olds), selected for ability and interest in science, to Nettlecombe Field Studies Council centre in Somerset on the eastern edge of Exmoor. Here they underwent an intensivecourse designed to stretch their enquiry skills well beyond levels expected for their year group. From theearly 1990s we went armed with the eight data-loggers and a crate of around 50 probes (plus a few Acorn computers). The motivating effect of this juxtaposition of new technology and nature, and the improvement in enquiry skills that resulted, encouraged me to look for enquirywork around the school grounds that might beenhanced by the use of data-loggers so that these benefits were not restricted to the ‘Nettlecombeexperience’. Over the years I have developed severalinvestigations, not all of which are appropriate in any given environment, but some of which are likely to be applicable, whatever the school’s circumstances. The realjoy of ecologicalinvestigations is that there is a great deal of scope for genuine uncertainty . V ariables are often hard to control and results are frequently ambiguous and inconclusive. Plants and animals seldom read the script. This can promote very productivediscussions with (and between) pupils, which will move on their thinking in testing hypotheses. As a science adviser I am very aware of the varying degree to which schools have access to safe habitats in which to study in this way . There is also a security consideration when leaving probes out for extended periods, but local conditions are seldom a total bar to this approach to scientificenquiry . Every schoolis different and has different opportunities and threats to ecological data-logging. I have visited schools where teachers felt their grounds to be of little (ecological) worth, only to discover secure and under-used outdoor areas, trees, lawns and sometimes abandoned ponds. I have suggested some activities below, suitable for pupils aged 11–16, that schools couldconsider when assessinghow their own grounds might be used (making, of course, the usual risk assessments). Most of the activities can becarried out with any ‘standard issue’ data-loggers such as those
Transcript
School Science Review, March 2006, 87(320) 69
Fearn Data-loggers in ecological enquiry
Data-loggers in ecologicalenquiry in school grounds
and beyondFrank Fearn
Ideas and hints on using data-loggers to enhance outdoor enquiries
ABSTRACTMost schools use data-loggers in science, oftento take readings in laboratory experiments. Theuse of data-loggers outside can improve thevariety and rigour in ecological enquiry in schoolgrounds. Four case studies illustrating outdoor enquiry-based applications, suitable for pupils aged 11–16, are presented: Pond enquiry; Mammal activity enquiry; Microenvironments inlog piles and compost bins; Sphere of influenceof trees. Hints and tips for successful outdoor data-logging are listed.
Nearly 15 years ago I heard of a new product beingdeveloped by the equipment supplier, Philip Harris,which would collect data, store them and downloadto a computer. At the time, my science department was rapidly increasing the use of graphing programs to display and analyse data, but teachers werebecoming concerned at the amount of time pupils were spending inputting results. The new data-logger seemed to be an ideal tool to overcome this problem. As things turned out, we must have beenone of the very first orders received by Philip Harris because they sent not one data-logger, but eight, onthe understanding that we would ‘road-test them’and present our findings both to the Associationfor Science Education (as a display at the AnnualMeeting) and to the Design Council (as a video).
I quickly found that some of the most interestinguses of this new tool were outside in the field. Our school had a tradition, each June, of taking a group of about 25 year 7 pupils (11/12 year-olds), selectedfor ability and interest in science, to NettlecombeField Studies Council centre in Somerset on theeastern edge of Exmoor. Here they underwent anintensive course designed to stretch their enquiryskills well beyond levels expected for their year
group. From the early 1990s wewent armedwith theeight data-loggers and a crate of around 50 probes (plus a fewAcorn computers). Themotivating effect of this juxtaposition of new technology and nature,and the improvement in enquiry skills that resulted,encouraged me to look for enquiry work around theschool grounds that might be enhanced by the use ofdata-loggers so that these benefits were not restrictedto the ‘Nettlecombe experience’. Over the years Ihave developed several investigations, not all ofwhich are appropriate in any given environment, but some of which are likely to be applicable, whatever the school’s circumstances.
The real joy of ecological investigations is that there is a great deal of scope for genuine uncertainty. Variables are often hard to control and results arefrequently ambiguous and inconclusive. Plants andanimals seldom read the script. This can promotevery productive discussions with (and between) pupils, which will move on their thinking in testinghypotheses.
As a science adviser I am very aware of thevarying degree to which schools have access to safehabitats in which to study in this way. There is alsoa security consideration when leaving probes out for extended periods, but local conditions are seldom atotal bar to this approach to scientific enquiry. Everyschool is different and has different opportunities and threats to ecological data-logging. I have visitedschools where teachers felt their grounds to be oflittle (ecological) worth, only to discover secureand under-used outdoor areas, trees, lawns andsometimes abandoned ponds. I have suggested someactivities below, suitable for pupils aged 11–16, that schools could consider when assessing how their own grounds might be used (making, of course, theusual risk assessments).
Most of the activities can be carried out withany ‘standard issue’ data-loggers such as those
70 School Science Review, March 2006, 87(320)
Data-loggers in ecological enquiry Fearn
supplied by Philip Harris, Data Harvest, LogIT,Pasco and others. Some data-control companies willmanufacture non-standard equipment for use in thefield and one example of this (Murtec) has also beenincluded.
Case study 1: Pond enquiry Why is the bottom of a pond a suitable place for amphibians to over-winter? A good way to set up a certain amount of cognitive conflict here is todiscuss the implications of falling in a (shallow) pond on a winter’s evening: this would seem to bea particularly bad place to be at that time of year. Pupils should realise they need data about air andwater temperatures overnight or over several days
to explore any hypothesis they develop. Questions will be raised about whereabouts in the pond thetemperature probe should be left, and, ideally, morethan one depth can be sampled. This may lead tosome supplementary thinking about whether someponds (depthwise) are more suitable than others. Figure 2 shows a typical set of results obtained usingtwo temperature probes, one placed in the pondwater and the other in the air above it (Figure 3).
The next question to be asked is: What is this telling you about the ability of amphibians to surviveoutside the pond as compared with in it? What moreinformation do you now need, and how are yougoing to collect it, to answer this question?
Hampshire ICT and science advisory teams are currently working with the South East Grid
Figure 1 Hampshire teachers on a training courseconsider enhanced use of a school pond.
Figure 3 A data-logger with temperature probes beside and in a pond.
Figure 2 Typical data for a pondin southern England in winter,obtained with a data-logger andtwo probes.
School Science Review, March 2006, 87(320) 71
Fearn Data-loggers in ecological enquiry
for Learning and Murtec Education to find ways of setting up permanent pond-monitoring stations,which will be capable of streaming informationdirectly on to the Internet for any school to use (seewebsites). This has followed on from a successfulbirdbox project (Figure 4) where three Hampshireschools have been able to compare data throughInternet access. Few schools have more than onepond, so the advantages of having access to datafrom several ponds is obvious.
Case study 2: Mammal activity enquiryWhen are wild mammals active (and why)? Theinitial stimulus can be a discussion about all thepossible reasons why the middle of the day is not the best time for many mammals to be active. Hypotheses can be made about the likely activityhabits of whichever mammal has its home in or near school grounds or the grounds of a field study centre. Various investigations using probes are possible: for example, dangling a sound probe over badger set
exits to pick up movement in and out of the set as theprobe is disturbed has proved to be very successful; with careful placing this can even work with rabbits. Recording the time mammal traps are triggered,again using sound probes, is also possible (see hints and tips below). It is well worth setting a light probeat the same time so that comparisons can be madebetween light levels and activity levels.
Case study 3: Microenvironments inlog piles and compost binsWhat are the local conditions in the log pile (Figure5), as typically developed in school grounds as asource of woodlice? Are dampness, temperature,and humidity different in different parts of the pileand does this affect the number of woodlice there? What do woodlice really prefer? (This can possiblylead into the standard choice chamber investigation.) If several data-loggers are set up around the logpile, each with a set of probes, the results can becompared after (say) 24 hours. Pupils could be askedto consider the importance of taking the results over the same 24-hour period, rather than re-positioning asingle logger each day for several days running.
There are a number of variations on this theme. For example, compost heaps can lead to a widerange of questions for investigation (see e.g. Sangand Frost, 2005) and containers can be placed inareas that have good security (for the equipment). As with the pond investigations, temperature at different depths and over several days can provide useful data.Conditions in a compost heap or bin (Figure 6) canbe monitored with temperature probes. This is best
Figure 4 The Hampshire Birdbox Project usedthese stations, designed (by Murtec) to provideinformation on bird activity and weather/light conditions at several sites, as well as live webcamimages. The information is then available for interrogation by any school wishing to test ahypothesis.
Figure 5 A log pile in school grounds kept as asource of woodlice.
72 School Science Review, March 2006, 87(320)
Data-loggers in ecological enquiry Fearn
done over an extended period (probably the longest setting available on the data-logger), as it does not require particularly frequent readings. The amount of heat generated by decomposition can be veryimpressive and comes as a great surprise to manypeople (Figure 7). Some teachers have reported ‘offthe scale’ temperature readings with this activity; Ihave not personally encountered readings as dramaticas this but such results would certainly generate anumber of interesting questions worthy of further investigation.
Case study 4: Sphere of influenceof treesA range of investigations relating to trees and their influence on local habitat can be carried out (Figure8). First-hand observation of the tree and plants living near it can be sufficient stimulus. Pupils arelikely to suggest light as the biggest factor in terms of influence of the tree canopy, but this is far fromthe end of the story. The ‘light’ question poses further questions to do with time of year (angle ofsun, in leaf or not) and it is likely that a range oflight-probe readings from different locations aroundthe tree will be required. If plants such as nettles aregrowing around the chosen tree (as well as beyondthe tree’s influence), comparisons can be made totest hypotheses such as ‘nettles under trees will needbigger leaves’. Is the ground more or less damp under a tree? An argument can be made for either assertion; most types of data-loggers have the optionof humidity probes.
Figure 6 A data-logger connected to temperatureprobes in a compost bin.
Figure 7 Changes intemperature in a compost heap over 80 hours. Dosuch temperatures really rise to over 100 °C or arethese anomalous results?
School Science Review, March 2006, 87(320) 73
Fearn Data-loggers in ecological enquiry
Hints and tips for successful outdoor data-loggingl Some data-logger manufacturers will provide
extension leads for probes. This can be usefulin improving security as it allows the data-logger itself to be placed some distance away;
for example under a bush, or even back in theclassroom if the site under investigation is nearby.
l Freezer bags will protect the data-logger fromthe weather and overnight dew.
l Some probes are ‘happy’ to be totally immersedin water while other makes are not (check theinstructions). Temperatures of different ponddepths can be obtained by strapping (with rubber bands) a probe to a (metre) stick, which can thenbe planted in the pond (or stream).
l Probes ‘sample’ at intervals. In general, if a data-logger is set to run for (say) 24 hours, it willsample every few seconds. This is sometimes a problem with sound-sampling as the soundmay be quite brief and so could fall between tworeadings. This is a useful point to discuss withpupils, who may be able to come up with partialsolutions, usually involving the use of a seconddata-logger.
l Don’t forget that you can plug more than one ofthe same kind of probe into a data-logger. For example, three temperature probes running at once can be very useful for some investigations.
l Digital cameras and webcams can be used toprovide useful background information. For example, in the tree investigations (Figure 8) apicture could be taken from a chosen spot eachday (or at least every few days) over a seasonor even a whole year. Additionally, a sequenceof pictures could be taken through the day that probes are in use.
Figure 8 A tree is an influential organism in ahabitat but is it simply a question of light andshade?
ReferenceSang, D. and Frost, R. ed. (2005) Teaching secondary scienceusing ICT. Hatfield:ASE/London: JohnMurray.
WebsitesIntroduction to the potential of data-loggers in scienceinvestigations:http://www.rogerfrost.com
Murtec Education:www.murtec-controls.co.uk
South East Grid for Learning (project officer: Christopher Davison [email protected]):http://www.segfl.org.uk/birdbox/
Frank Fearn is a general inspector/adviser for science for Hampshire Inspection and Advisory Service(HIAS). He has been head of science in a middle school in Somerset and a secondary school in Tamesideand has taught science since 1978. He sits on the Education, Training and Careers Committee of the BritishEcological Society. Email: [email protected]
