Introduction to the Workshop: Identifying and Clarifying Nanoscience Learning Goals

Transcription

1 [Fr the wrkshp hsted by University f Michigan and SRI Internatinal, June 14-16, 2006, in Menl Park, CA] Intrductin t the Wrkshp: Identifying and Clarifying Nanscience Learning Gals What is the purpse f this wrkshp? Nanscience is a new and emerging field that has made substantial scientific breakthrughs in recent years. New infrmatin and technlgies resulting frm this research will cntinue t have brad scietal implicatins in many fields, including healthcare, manufacturing, agriculture, fd, water, energy, and the envirnment. T understand the new discveries and technlgies resulting frm nanscience research, and thus be capable f infrmed citizenship, we need a ppulatin with a high degree f science literacy. It is the respnsibility f ur natinal, state and lcal educatin leadership t prepare a much larger crss-sectin f ur ppulatin with the science and engineering knwledge required t functin in a highly technlgical sciety and t maintain the mmentum f discvery and innvatin that will sustain ur ecnmic prsperity. Unfrtunately, n internatinal studies f educatinal perfrmance in science and mathematics, U.S. high schl graduates ranked near the bttm (AAAS, 1990). T meet this natinal need and address this crisis, the Natinal Science Fundatin has funded varius prjects t create materials that can infrm children and the public abut nanscience and change the way science educatin is taught in this cuntry. Develpers ften struggle as they chse and priritize the cncepts n which t fcus, wrk t frame these cncepts in terms f learning gals, align these learning gals with natinal standards, and sequence these majr cncepts s 7 th -12 th grade students in science can develp a deep understanding f these ideas. Teaching nanscience withut a fundatin f learning gals is a challenge fr practitiners and teachers; therefre, we are cnvening as leading experts in nanscience, the learning sciences, and science educatin t begin t d this wrk. Why emphasize learning gals? We will integrate ur learning gals with learning gals based n the natinal standards in rder t help students in grades 7-12 develp a deep understanding ver time f scientific ideas related t nanscience. Accmplishing these gals will supprt the varius natinal grups wh have undertaken the task f develping educatinal materials and prfessinal develpment experiences fr nanscience educatin. Aligning all parts f the system t learning gals fsters the develpment f instructinal tls and resurces, educatinal experiences fr teachers, research studies, and plicies that are fcused n imprving student learning and achievement. Thus, identifying a set f agreed upn learning gals fr nanscience will ensure that all cmpnents f the educatin system, including curriculum, instructin, and assessment, will be aligned. What will this wrkshp entail? At this wrkshp, we will identify, elabrate and reach a cnsensus abut the cre cncepts and principles fr nanscience educatin. Cre cncepts and principles represent the big ideas f 1

2 [Fr the wrkshp hsted by University f Michigan and SRI Internatinal, June 14-16, 2006, in Menl Park, CA] the field. Big ideas 1) help learners understand a variety f ideas abut nanscience, 2) prvide insight int the develpment f the field r have a key influence n explaining the majr ideas in the dmain, 3) prvide ideas/mdels t explain a range f phenmena, and 4) allw learners t intellectually make individual, scial, and plitical decisins regarding science and technlgy. Tgether, we will discuss these big ideas and turn them int learning gals that specify what students are expected t learn and be able t d with imprtant cncepts. In the wrkshp, we will cme t a cnsensus abut learning gals as we: Identify and clarify the majr cncepts and principles f nanscience; Clarify the meaning f these cre cncepts and principles; Specify the learning gals that emerge frm the majr cncepts and principles; Determine hw these learning gals align with natinal standards; and Establish where related natinal standards d nt yet exist. One f the main tasks at the wrkshp is fr small grups f participants t unpack the nanscience learning gals. This invlves breaking apart, expanding and elabrating n the cmplex ideas stated in the relatively succinct standards. Unpacking als invlves identifying the necessary teacher knwledge, as well as prir knwledge and pssible miscnceptins that students might have, which ultimately help t prvide clarity t the learning gal. As part f ur wrk, we will als identify phenmena that help illustrate the learning gal. One detailed example f what we mean by unpacking a learning gal is prvided in the appendix. Aarn Rgat, Je Krajcik, Yael Shwartz frm the University f Michigan, and J Ellen Rseman frm Prject 2061 spent many hurs unpacking this benchmark. Althugh we d nt expect this same level f detail t be accmplished at the wrkshp, we hpe t achieve this level eventually. At the cnclusin f the wrkshp, we wuld like t have rugh drafts f 4-6 unpacked learning gals. Ultimately, we will create a learning prgressin fr each f the nanscience learning gals develped at the wrkshp. A learning prgressin is a sequence f successively mre cmplex ways f thinking abut an idea that might reasnably fllw ne anther as students g thrugh schl. What are the prjected utcmes? The dcuments we will create include the fllwing: A Fundatins mngraph that will speak t teachers and administratrs A webpage with infrmatin fr materials develpers, members f the NSEC, MRSEC, NISE, NCLT and NSF cmmunities, and researchers A jurnal article that will address the issues f researchers and develpers We will als present ur results at varius natinal cnferences. Tgether, these dcuments and presentatins will infrm varius grups f the majr learning gals in nanscience. The prducts f this wrkshp will address three audiences: 2

3 [Fr the wrkshp hsted by University f Michigan and SRI Internatinal, June 14-16, 2006, in Menl Park, CA] Classrm teachers and administratrs Nanscientists and educatrs interested in cntributing t the develpment f materials fr students Researchers in science educatin/learning sciences We d nt suggest that these dcuments will be the final wrd n nanscience learning gals, nr that the learning prgressin we prpse will be the nly ne pssible. Instead, ur effrts will serve t pen the cnversatin n this imprtant wrk, and will help identify areas f research necessary t supprt the learning trajectry that is develped. Appendix The benchmark belw is frm the Flw f Matter and Energy sectin f The Living Envirnment (AAAS, 1993). We purpsely chse an example unrelated t nanscience. Full Benchmark (AAAS 6-8: 5E2): Over a lng time, matter is transferred frm ne rganism t anther repeatedly and between rganisms and their physical envirnment. As in all material systems, the ttal amunt f matter remains cnstant, even thugh its frm and lcatin change. Idea A (5E2) Over a lng time, matter is transferred frm ne rganism t anther repeatedly and between rganisms and their physical envirnment. What d kids need t understand here? What are the general interactins that we are talking abut here? All living rganisms interact with their physical envirnment in rder t survive and functin. One f the very basic interactins is the transfer f matter. The substances that get in the rganism underg chemical reactins (which are essential fr the rganism's survival). In thse chemical reactins the arrangement f atms is changed and new substances are prduced (frm ld nes), but the ttal amunt f matter remains cnstant (see Idea B). Sme f the prducts are transferred ut f the rganisms bdy t the envirnment. - What is the matter being transferred here? Carbn, xygen and hydrgen (shuld we mentin nitrgen?) are all different types f atms that are transferred between rganisms and between rganisms and the envirnment. Hwever, carbn is a central cmpnent f all the matter being transferred. Since this transfer f matter happen cntinuusly, repeatedly, and endlessly, it is ften described as a cycle. Thus we ften refer t this transfer as the carbn cycle. In this idea, we fcus mainly n parts f the carbn cycle that invlve living systems (any systems invlving rganisms e.g., a human bdy, a plant, a marine ecsystem, a land ecsystem). Hwever, if the carbn cycle is mentined, students wuld need t realize the part we are lking at is nly a piece f the carbn cycle (nt the whle thing). - What are the specific interactins that we are talking abut? Phtsynthesis: CO 2 gets int plants thrugh the air in the envirnment via the leaves and H 2 O gets int the plant thugh grund water in the envirnment via rts. CO 2 and H 2 O underg chemical reactin t prduce fd fr the plant (specifically glucse, C 6 H 12 O 6 ; see 5E1 fr mre n fd) and O 2. O 2, a prduct f this reactin, is released back int the envirnment. This chemical reactin requires energy, which is prvided by sunlight. The sugars can be used fr building plant material r fr its energy needs. (refer t 5E1) Eating and digesting: All living rganisms need fd. Sme animals eat nly plants, and sme eat ther animals. The carbn atms that cmpsed the plant material are nw transferred t ther animal s bdy. Digesting fd means that the prteins, carbhydrates 3

4 [Fr the wrkshp hsted by University f Michigan and SRI Internatinal, June 14-16, 2006, in Menl Park, CA] and fats are being brken dwn int simpler and smaller mlecules that can be absrbed by the cells. Lng chains f prteins are being brken dwn t small mlecules f amin acids, carbhydrates are being brken dwn t glucse and fats and ils are being brken dwn t fatty acids. In all rganisms (including plants) glucse (that cmes frm fd) and xygen (inhaled by the respiratry system) are invlved in a chemical reactin that supplies the energy needs f all cells. In a series f chemical reactins glucse and O 2 react, and CO 2 and water are prduced. The CO 2 is being released t the atmsphere, and there it can be absrbed again by plants fr the prductin f mre fd. Decaying: When leaves r fruits fall n the earth, and when rganisms such as plants r animals die, the varius substances in them underg decmpsitin reactins (sme f which are xidatin reactins see 5E3). In sme decmpsitin reactins, CO 2 is being released t the atmsphere. Similarly, dead marine rganisms sink t the bttm f the cean and the carbn atms in their bdies are used t prduce sediments rcks. Students need t understand nt nly the particulate nature f matter and the mlecular nature f chemical reactins (AAAS5-6: 4D1, & 4D8?, NRC 5-8: B1/2; AAAS6-8), but als the cnservatin f matter during a chemical reactin: the number f atms stays the same n matter hw they are rearranged (AAAS5-6; 4D7). In a clsed system, the mass f all the substances befre and after the reactin is the same. What time scale are we talking abut? Sme interactins between rganisms culd be ver a perid f days, such as rganisms eating ther rganisms. But fr sme interactins between rganisms and the envirnment this culd be ver a perid f thusand f years (e.g. transfrmatin f plant and animal matter int sedimentary rcks). Teachers' backgrund One way t demnstrate the cntinuity f these transfers is the carbn cycle. As this benchmark fcuses n rganisms, nly the rganic part f the cycle needs t be emphasized. The key chemical reactins are phtsynthesis (in plants), glyclysis (in all cells), and decmpsitin f fd t smaller mlecules. Smetimes the ntin f the central idea is being lst in the small details. Fr example, it is nt necessary at this level t describe the chlrphyll, PGA, light phase r dark phase f phtsynthesis, but t fcus n understating the essence f the reactin. The carbn cycle refers t the cycling f carbn in nn-living surces as well as living surces. Nn-living surces include rcks, fssil fuels, CO 2 in the atmsphere and CO 2 sluble in water, but we will fcus n the living cmpnents Prerequisite knwledge Atms and mlecules: Atms frm mlecules and mre than ne kind f atm may frm mlecules. All substances are cmprised f mlecules (AAAS5-6: 4D1) Elements: Atms f a particular element are the same, and the atms f different elements are different (4D1). Different atms have different reactive prperties (AAAS5-6: 4D6) Chemical reactin: a rearrangement f the atms and mlecules f the reactants t prduce new mlecules (NRC5-8:B1/2; AAAS5-6, 4D8?). The ttal amunt f atms f each element remains cnstant (Cnservatin f matter, AAAS5-6: 4D7). Students much realize this is an pen system and must knw what an pen system vs. a clsed system means. Chemical reactins invlve energy changes. Energy can be released during sme chemical reactins, and energy is required in rder t enable ther chemical reactins t ccur. Fd is needed by all rganisms in rder t supply energy and as building material. Plants make their wn fd by using CO 2 and sunlight t prduce glucse. Glucse is used by all ther rganisms in their cells in rder t release energy. 4

5 [Fr the wrkshp hsted by University f Michigan and SRI Internatinal, June 14-16, 2006, in Menl Park, CA] Different rganisms interact with each ther in prducer/cnsumer r predatr/prey type interactins. Alternative cnceptins/cnceptual challenges 1. Yung students tend t think f living systems as discnnected frm the natural wrld (n citatin, just infrmal knwledge frm a teacher/researcher) 2. It is difficult fr students t describe bilgical phenmena in terms f chemical substances and chemical reactins. Fr example, fr them respiratry is inhaling and exhaling, but nt the xidatin prcess f glucse. Mre generally, it was fund that kids have difficulties t make the cnnectins between chemical knwledge and bilgical knwledge even in cases when they were taught by the same teacher (n citatin, just infrmal knwledge frm a teacher/researcher). 3. Students at this age have a very central view; they think as humans as the centre f universe. It is difficult fr kids t understand the huge imprtance f plants (n citatin, just infrmal knwledge frm a teacher). 4. Students tend t think that the surce f bimass f plants is sil nt phtsynthesis (n citatin, just infrmal knwledge frm a teacher). 5. Students tend t mix between phtsynthesis and glyclysis (n citatin, just infrmal knwledge frm a teacher/researcher). 6. It is difficult fr students t maintain bth aspects f chemical reactins, the rearrangement f substances and the energy changes. Hwever, this is crucial t understand why certain chemical reactins take place at all (n citatin, just infrmal knwledge frm a teacher). Idea B (5E2) As in all material systems, the ttal amunt f matter remains cnstant, even thugh its frm and lcatin change. What kids need t knw here? What des remains cnstant mean? As learned in 7 th grade, during a chemical reactin the amunt f matter remains cnstant. This is als true when referring t any chemical reactins that ccur in living systems. Fr example, we can see that all 6 atms f carbn in glucse becme incrprated int 6 mlecules f CO 2 in the prcess f xidatin f glucse (i.e. respiratin). Likewise, in the prcess f phtsynthesis the carbn atms frm 6 mlecules f CO 2 are incrprated int ne mlecule f glucse, C 6 H 12 O 6. It might be gd fr students t have a Leg kit mdel, appreciating that the ttal number f Legs remains essentially cnstant. Students shuld appreciate that living rganisms can be viewed as pen cntainers in which lts f chemical reactins ccur, that if we culd keep track f all the atms entering, leaving, and staying put we wuld see that the ttal amunt remains cnstant, even thugh frm and lcatin cntinually change. What matter is being cnserved? In living systems and nn-living systems this cnservatin f matter can be illustrated by the carbn cycle. The amunt f carbn atms remains cnstant; they nly change frm (they cmbine t frm new arrays f mlecules) and lcatin (i.e. the place that matter exists such as in the air, in a plant cell, r in an animal cell, r even in a different lcatin inside f a multicellular rganism). The change f frm always invlves a chemical reactin (see Idea A). - Fr example, during a certain perid f time, carbn atms are depsited in rcks, then disslve in water, and then are used fr phtsynthesis by seaweed r algae (that can use CO 2 absrbed frm water). These algae can be eaten by anther rganism and the carbn atms becme part f the fd chain and are used fr building blcks f the rganism bdy and fr prducing glucse. Oxidizing glucse (t supply energy) will release CO 2 t the atmsphere; this CO 2 can be used again fr phtsynthesis. When an rganism dies, 5

6 [Fr the wrkshp hsted by University f Michigan and SRI Internatinal, June 14-16, 2006, in Menl Park, CA] sme f the carbn atms will find their way t earth, air and water again. Students can be expected t fllw the buncing ball. Again, students need t understand nt nly the particulate nature f matter and the mlecular nature f chemical reactins (AAAS5-6: 4D1, & 4D8?, NRC 5-8: B1/2; AAAS6-8), but als the cnservatin f matter during a chemical reactin: the number f atms stays the same n matter hw they are rearranged (AAAS5-6; 4D7). In a clsed system, the mass f all the substances befre and after the reactin is the same. In the cntext f phtsynthesis, the number f carbn atms stays the same despite the fact that a new mlecule, sugar, is frmed frm carbn dixide. Hwever, since this is nt a clsed system, xygen gas, a prduct f the reactin, can leave the plant and diffuse int the atmsphere. In the cntext f digestin, sugar eaten by animals reacts with xygen t prduce carbn dixide. Again, the carbn atms are cnserved and sme mlecules (i.e. carbn dixide) spread thrughut the atmsphere and sme disslve in water because it is an pen system. Teachers' backgrund This idea presents cnservatin f matter (yes, but let s restrict it t carbn) in a glbal perspective. [In Idea A, emphasis was placed n the rle f chemical reactins in matter being transferred, Here, the ntin f a ttal amunt f atms, changing frms and lcatin is the central ne]. Cnservatin f matter can be described qualitatively in the carbn cycle, but als quantitatively (by cunting the number f atms f each element in the reactants and prducts f a given chemical reactin). We dn t expect students t be able t balance equatins but nly t realize that the ttal number f carbn atms stays the same, even thugh the distributin in different carbn-cntaining mlecules may change frm ne time t the next. Understanding this ntin f cnservatin f matter in living systems can be challenged by a questin: culd it be that carbn atms in my bdy nce were in a dinsaur's bdy? Prerequisite knwledge Understanding cnservatin f matter during a chemical reactin (AAAS5-6: 4D7) Being able t identify different symbls f elements in a given reactin and t cunt the number f atms f each element All prerequisite knwledge as described fr Idea A Alternative cnceptins/student challenges Understanding this idea requires thinking abut the universe including living systems as a united system. This kind f "systematic thinking" is very difficult fr kids. References American Assciatin fr the Advancement f Science (AAAS). (1990). Science fr all Americans, Prject New Yrk, Oxfrd University Press. American Assciatin fr the Advancement f Science (AAAS). (1993). Benchmarks fr science literacy, Prject New Yrk, Oxfrd University Press. 6