Executive Function:Concepts, Assessment & InterventionPeter K. Isquith, Ph.DGerard A. Gioia, Ph.D.Robert M. Roth, Ph.D.
Interest in Executive Function in Children600 5 articles in 1985 14 articles in 1995500400 501 articles by 2005300– Bernstein & WaberExecutive Function inEducation, 20072001000198519952005
Plan What are Executive Functions? How do we identify them? What is the developmental course? What is the brain basis? How do they manifest in clinical disorders?
Executive FunctionDefinitions Planningand sequencing of complex behaviors Ability to pay attention to several components atonce Capacity for grasping the gist of a complexsituation Resistance to distraction and interference Inhibition of inappropriate response tendencies Ability to sustain behavioral output for relativelyprolonged periodsStuss & Benson, 1984
Orchestration of basic cognitiveprocesses during goal-orientedproblem-solvingNeisser, 1967
Functions of the “Orchestra”Functions of the “Conductor” Perception Inhibit Attention Shift Flexibly Language processes Modulate Emotions Visual-spatial processes Initiate Memory Working Memory Sensory inputs Plan Motor outputs Organize Knowledge & skills social non-social Self-monitor & evaluate
Methods of Assessing EFMolarMicroGeneticsStructural s70Count the number of moves6560Goal:555045Problem:4034Inhti biShif tEmootinalMWlsrgorria/Oni tneotaaMPlM
Measurement of Executive Functions Executive Functions are dynamic, fluid All tests and tasks require content andEF Many tests are too structured toobserve EF Examiner as“Executive”
Methods of Assessing EFAdvantages MolarLevel Increased specificity of process Increased task control and internal validity Macro Level Opportunity for EF in dynamic action Increased ecological validity
Methods of Assessing EFDisadvantages Molar Level Fragmentation of EF out of context Decreased ecological validity Influence of “content” variance Macro Level Decreased control of environmentalcontingencies Respondent variance (rating scales)
Performance Tests tappingExecutive Functions VerbalFluency / Figural Fluency Stroop Color-Word Interference Test Rey-Osterrieth Complex Figure Tower of Hanoi / Tower of London Wisconsin Card Sorting Test Mazes Trail Making Continuous Performance Tests
Rey Osterrieth Complex Figure
The Rey-Osterrieth Complex Figure
9-year-old with Reading DisorderCopyRecall
8 year-old boy with Asperger’sCopyRecall
10 year-old boy with ADHD-CRecallCopyRecall
10 year old with ADHD-ICopyRecall
The Tower of London
Tower of London 6 Move
Count the number of movesGoal:Problem:34Illustration of a Tower of London taskadapted for fMRIfMRI during the hard condition relative to theeasy task condition (difficulty being basedon number of moves required to solveproblem) in a healthy adult, showingprominent frontal lobe activationFrom the Brain Imaging Laboratory at Dartmouth Medical School; Roth et al. (2006)
Wisconsin Card Sorting Task
Stroop Task: Inhibit
Illustration of a CountingStroop task adapted for fMRIfMRI during the incongruent conditionrelative to the congruent condition in agroup of 13 healthy adults, showingprominent activation of the dorsalanterior cingulate gyrusFrom the Brain Imaging Laboratory at Dartmouth Medical School (Roth et al., 2006)
Limitations to Performance Tests: EF tests are molar, tapping several EF and non-EFfunctions that can be disrupted in many ways Differences in cognitive ‘style’ or ability can affectEF performance regardless of EF Sensitivity/Specificity limited- Pts who should haveEF deficits do well on EF tests; EF performancenot sensitive to frontal vs extra-frontal lesions Discriminant Validity- If EF tasks are impaired inseveral disorders, then EF’s are not helpful indistinguishing between disordersPennington & Ozonoff, 1996
Impetus: Clinical need for external validation,ecological validity, real-world anchor Common parent descriptions Performance tests versus rating scales
BRIEF ConspiratorsGerard A. Gioia, Ph.D.Lauren Kenworthy, Ph.D.Children’s National Medical CenterPeter K. Isquith, Ph.D.Robert M. Roth, Ph.D.Dartmouth Medical SchoolSteven C. Guy, Ph.D.Independent PracticeKimberly Andrews Espy, Ph.D.Vice Provost, University of Nebraska, Lincoln
Rating scales of everydayexecutive behaviors Adult: Frontal Systems Behavior Scale (FrSBe) Dysexecutive Questionnaire (DEX) Behavior Rating Inventory of Executive Function(BRIEF-Adult Version) Child Behavior Rating Inventory of Executive Function(BRIEF) Dysexecutive Questionnaire-Children’s (DEX-C)
A BRIEF Geneology200020032004200?2005
BRIEF BasicsBRIEFBRIEF-P BRIEF-SRBRIEF-AItems /Scalesα86 / 863 / 580 / 880 / 9.80 - .90’s.80 - .90’s.80 - .90’s.80 - .90’sRetest.80 - .90’s.80 - .90’s.80 - .90’s.80 - .90’sInterraterCovaryP - T r .30P- Tr .17 - .28S - P .50S - T .25Self-Informant .67BASC, CBCL,ADHD-IVCBCL,ADHD-IVCBCL,BASC,ADHD-IV,CHQBeck, DexFrSBe,CAD, STAIADHD, LD,TS, ASD,Frontal lesion,PKU, TraumaASD,ADHD,Language,LBWClinicalGroupsADHD, ASD,Anx/Dep,T1DMADHD, MCI,MS, TBI,Epilepsy
BRIEF Clinical Studies ADHD - Jarratt et al, 2005; Loftis, 2005; Viechnicki, 2005; Lawrence et al., 2004; Blake Greenberg, 2003; Palencia, 2003; Kenealy, 2002; Mahone et al., 2002Disorders - Gioia et al., 2002; Pratt, 2000.ReadingAutism Spectrum Disorders - Gilotty et al., 2002; Gioia et al., 2002Bipolar Disorder vs ADHD - Shear et al., 2002Tourette’s Syndrome - Mahone et al., 2002; Cummings et al., 2002Traumatic Brain Injury - Landry et al., 2004; Brookshire et al., 2004; Gioia et al.,2004; Mangeot et al., 2002; Vriezen et al., 2002; Jacobs, 2002; Spina Bifida and Hydrocephalus - Burmeister et al., 2005.; Brown, 2005;Mahone et al., 2002. Obstructive Sleep Apnea - Galactosemia - Antshel et al., 2004Childhood onset MS - McCann, et al., 2004Sickle Cell - Kral et al., 200422q11 Deletion - KileyKiley-Brabeck,Brabeck, 2004PKU - Antshel et al., 2003Frontal lesions, PKU & Hydrocephalus - Anderson et al., 2002 Beebe, 2004, 2002
BRIEF: Inhibit Isimpulsive Has trouble stopping when silly Has to be closely supervised Does not think before doing
BRIEF: Shift Is stubborn Cannot get a disappointment off their mind Resists accepting a different way to solve aproblem Becomes upset with new situations
BRIEF: Emotional Control Overreacts to small problems Explosive, angry outbursts Tearful easily Mood changes frequently
BRIEF: Initiate Does not take initiative Is not a self-starter Needs to be told to begin a task evenwhen willing Has trouble coming up with ideas for whatto do in play or free time Lies around the house a lot (couch potato)
BRIEF: Working Memory Is absent-minded When given three things to do, remembersonly the first or last Trouble with multistep chores
BRIEF: Plan/Organize Good ideas but can't get the job done Written work poorly organized Starts project without the right materials Trouble planning for future play activities Underestimates time needed to completetasks
BRIEF: Monitor Doesn't ask for help when needed Doesn't check work for mistakes Makes careless errors Unaware of how behavior affects others Leaves work incomplete
BRIEF: Organization of Materials Leaves playroom a mess Loses lunch box, lunch money,permission slips, homework Cannot find clothes, glasses, shoes,toys, etc Backpack is disorganized
BRIEF StructureMetaCognitionMonitorOrg of MaterialsPlan/OrganizeWorking MemoryInitiateEmotional ControlBehavioralRegulationShiftInhibit
PFA of Parent BRIEF With BASCParent Rating Scale (n 80)ScalesFactor1 2 3 4Working memoryPlan/organizeMonitorInitiateBASC attention problemsOrganization of MaterialsBASC hyperactivityBASC conduct problems.904.878.799.791.698.516.720.607
PFA of Parent BRIEF With BASCParent Rating Scale(Cont.)ScalesFactor1 2 3 4BASC anxietyBASC depressionBASC somatizationBASC atypicalityBASC withdrawalInhibitEmotional controlBASC aggressionShift.764.696.661.467 .531.521-.769-.686-.565-.392
Methods of Assessing EFMacroMicroGeneticsStructural unt the number of moves6560Goal:555045Problem:4034Inhti biShif tEmootinalMWlsrgorria/Oni tneotaaMPlM
Plan What are Executive Functions? How do we identify them? What is the developmental course? What is the brain basis?How do they manifest in clinical disorders?
Development of Executive Functions:Plan/Organize/Monitor3–32 yrsEmotional Modulation3–? yrsVerbal Working Memory2–13 yrsNonverbal Working MemoryInhibit3-24 mo0-?
Change in effect Size Across Childhood onPerformance Tests of Executive FunctionRomine & Reynolds, 2005; Applied Neuropsychology
Adolescence"Youth today love luxury. They have bad manners,contempt for authority, no respect for older people,and talk nonsense when they should work. Youngpeople do not stand up any longer when adultsenter the room. They contradict their parents, talktoo much in company, guzzle their food, lay theirlegs on the table and tyrannize their elders“Socrates c 400 BC
Adolescence:Not just forhumans anymore Many species show an adolescent period Acquisition of skills permit survival away fromparents Increased affiliation with peers Increased risk taking behaviors May reflect evolutionary need to avoid inbreeding
Risk Taking Behavior Adolescentsare highest sensation seeking& risk taking group As much as 80% show risk behaviors in amonth 50% engage in drinking & driving,unprotected sex, illegal drug use, minorcriminal activity (Arnett, 1992)Is Risk Taking Normal
Supreme Court of the United States--------------------------------- --------------------------------DONALD P. ROPER, SUPERINTENDENT,POTOSI CORRECTIONAL CENTER,Petitionerv.CHRISTOPHER SIMMONS--------------------------------- --------------------------------On Writ Of Certiorari To TheSupreme Court Of Missouri--------------------------------- --------------------------------BRIEF FOR THE AMERICAN PSYCHOLOGICALASSOCIATION, AND THE MISSOURIPSYCHOLOGICAL ASSOCIATION ASAMICI CURIAE SUPPORTING RESPONDENTwww.apa.org/psyclaw/roper-v-simmons.pdf
SUMMARY OF ARGUMENTAt ages 16 and 17, adolescents, as a group, are not yetmature in ways that affect their decision-making.Behavioral studies show that late adolescents are less likelyto consider alternative courses of action, understand theperspective of others, and restrain impulses. Delinquent,even criminal, behavior is characteristic of manyadolescents, often peaking around age 18. Heightened risktaking is also common. During the same period, the brainhas not reached adult maturity, particularly in thefrontal lobes, which control executive functions of the brainrelated to decision-making. Adolescent risk-taking oftenrepresents a tentative expression of adolescent identity andnot an enduring mark of behavior arising from a fullyformed personality. Most delinquent adolescents do notengage in violent illegal conduct through adulthood.
Plan What are Executive Functions? How do we identify them? What is the developmental course? What is the brain basis?How do they manifest in clinical disorders?
The “Conductor Metaphor” meets the “Frontal Metaphor”ConductorOrchestra
Phineas Gage: 9/13, 1848 in Ludlow, VT 3’ tampingiron shot throughleft cheek and exited leftfrontally Destroyed much of leftfrontal lobe
Phineas Gage: A changed man“He is fitful, irreverent, indulging at times inthe grossest profanity, impatient ofrestraint or advice when it conflicts withhis desires; at times pertinaciuouslyobstinate yet capricious and vascillating.His friends and acquaintances said hewas no longer Gage”Harlow, 1868
STRUCTURAL BRAIN CHANGESLenroot et al. (in press; Neuroscience and Biobehavioral reviews)
Plan What are Executive Functions? How do we identify them? What is the brain basis and developmentalcourse of executive functions? How do they manifest in clinical disorders?
Disorders of Executive Function No singular, core disorder Symptom onset delayed due to prolongeddevelopment & environmental demand Performance on standardized tests oftenappropriate Discrepancy between ability and performance Fluid social domain often most challenging
Diagnostic DRADASD(NLD)MREpilepsyTBILDSLDOHIOrthoSLPDeafVis ImpPDDMR/IDTBIEBD
CLINICAL APPLICATIONS:Pediatric ADHD
Recent ConceptualizationsWith a better understanding of brain-behaviorrelationships, particularly the frontal lobes: ADHD is undergoing further redefinition interms of a disorder of the executivefunctions (EF) (Barkley, 1997, 2000; Brown, 1999;Denckla, 1996; Pennington & Ozonoff, 1996) primacy of“attention” is being questioned.
DSM-IV Diagnostic Criteria: ADHD PredominantlyInattentive Type6 or more maladaptive and developmentallyinappropriate Symptoms for 6 monthsWorking Memory Often fails to give close attention to details ormakes careless mistakes in schoolwork, work orother activitiesWorking Memory Often has difficulty sustaining attention in tasks orplay activitiesWorking Memory Often does not seem to listen when spoken todirectlyWorking Memory Often does not follow through on instructions andfails to finish schoolwork, chores, or duties in theworkplace
DSM-IV Diagnostic Criteria: ADHD PredominantlyInattentive TypePlan/Organize Often has difficulty organizing tasksWorking Memory Often avoids, dislikes, or is reluctantOrganizationInhibitory ControlWorking Memoryto engage in tasks that requiresustained mental effort Often loses things necessary fortasks or activities Is often easily distracted byextraneous stimuli Is often forgetful in daily activities
DSM-IV Diagnostic Criteria, ADHD Predominantly Hyperactive,Impulsive Type6 or more maladaptive and developmentallyinappropriate Hyperactivity Symptoms for 6monthsInhibit? Arousal?Inhibitory control Inhibitory control Inhibitory control Inhibitory controlInhibitory control Often fidgets with hands or feet or squirms in seatOften leaves seat in classroom or in othersituations in which remaining seated is expectedOften runs about or climbs excessively insituations in which it is inappropriate (adolescentsmay be subjective)Often has difficulty playing or engaging in leisureactivities quietlyIs often “on the go”go” or acts as if “driven by a motor”motor”often talks excessively
Pennington & Ozonoff, 1996ADHD Studies:WCST PersevTrails B TimeStroop TimeMazesLetter FluencyCategory FluencyTowerMotor ct.188.8.131.52.271.08.85
Pennington & Ozonoff, 1996 15 of 18 studies found ADHD worse thanControls on 40 of 60 putative EF tasks 10/13 found NO differences on non -EF tasks Same analysis in CD and TS revealed EFtask deficits ONLY with comorbid ADHD EF tasks do better at excluding normals thanat including ADHD EF alone is not sufficient to explain ADHD?
Reading Disability and ADHD: Is there aCommon Deficit in Executive Function? 151 Controls, 104 ADHD, 109 RD, 64 ADHD RD 5 Factor Battery of EF and Reading tasks:RDADHDLanguageProc Speed WMShiftInhibitLindamoodOrtho CodingNonwordsPig LatinStroop WordStroop ColorStroop CWCodingSymbol SrchTrails BWCSTCPT ComCPT OmStop Sig-RT-RT VarCount spanSent spanArithmeticDigits FDigits BWillcutt, Pennington, Olson, Chhabildas & Huslander, 2005
Factors support multiple, related EF domains ADHD: inhibit, speed, WM RD: Language, speed, WM, inhibit ADHD RD: Additive Deficits ADHD/RD show similar EF performance Slow & Variable processing speed may be acommon deficit No plan, organize, monitor tasks includedWillcutt, Pennington, Olson, Chhabildas & Huslander, 2005
Rating Scale Profiles
Parent vs Adolescent Reports in g MaterialsADHD-I ParentADHD-I SRADHD-C ParentADHD-C SR
M ean s and S tan d ard D eviation s for B R IE FC om posite an d C lin ical S calesB R IE F S cale/ Ind exPlaceb oM ethy lphenidatetPGEC6 7.94 ( 8.3 6)5 9.53 (11.7 9)3 .13.0 06B eh av. R eg. In dex6 7.18 (10.4 7)5 9.41 (12.0 7)2 .49.0 24M etacog. Index6 5.71 ( 7.9 9)5 7.94 (11.9 2)3 .41.0 04In hibit6 7.88 (10.6 5)5 9.06 (13.0 9)2 .94.01Sh ift6 1.35 (12.5 8)5 7.12 (12.8 3)1 .19.25E m otional C o ntrol6 2.35 ( 8.1 2)5 6.47 (10.0 9)2 .11.0 51Initiate64 .4 7 ( 8.5)5 6.63 (11.5 3)2 .93.01W o rking M em ory6 9.53 (7.5 8)6 0.47 (12.6 8)3 .34.0 04P lan / O rgan ize6 3.24 (9.7 9)5 6.35 (13.3 5)2 .72.0 15O rgan o f M aterials5 9.29 (10.7 6)5 3.41 ( 9.7 3)2 .31.0 34M o nito r6 5.71 (7.9 9)5 8.41 (11.0 2)2 .52.02N ote: M ean T scores are rep orted .D oub le b lind p lacebo -con trolled cro ssover d esig n. n 17K unin -B atson, A . (2 001) E ffects o f m ethy lp hen idate on neu ro psychologicalfun ction ing in children w ith attention deficit hyp eractivity disorder.U npu blish ed dissertatio n, Fin ch U niversity of H ealth Sciences/ T h e C hicag oM ed ical Sch ool.
Executive Functions in Adult ADHDSelf Report Executive Function in Unmedicated (n 27) and Medicated(n 16) Adults with ADHD, and Healthy Controls (n 4030tbiihInEmlorrottiononCMallfneoSif thSiotBiederman, Fried, et al., unpublished datarlsozeitaiinierem rg aontInaMMMg/OkfsnnioakTanPloroitWzaiangOrteit ayor
Pennington & Ozonoff, 1996ASD Studies:WCST PersevWCST CatsTrails B 07-Inhibitory deficits prominent in ADHD-Shift deficits prominent in ASD
In Sum: Performance tests and rating scales showprofile differences between ADHD, RD andASD groups BUT also common deficits These profiles cut across age and gender Tests and scales are complementary:micro/molar to macro Neither tests nor scales of EF are necessaryor sufficient to diagnose conditions EF is not a diagnosis; EF is a function
BRIEF & Brain Disease:Anderson, Anderson, Northam, Jacobs & Mikiewicz, 2002 44 PKU 45 Hydrocephalus 20 Frontal Lesion (8 prenatal, 12 acquired) Neuropsychological testing, includingperformance EF tests, showed nodifferences between groups
5045403530ControlPKUHYDFL2520151050BRIMIProportion of Children in Clinical Groups with T 65
Correlations between Measures and High-Stakes Test scoresMeasureCodingSymbol SearchLetter–NumberMCAS English.47***.42***.44***NEPSY TowerD-KEFS InhibitionD-KEFS Inhibition–SwitchBRIEF BRIBRIEF MIMCAS .20–.46***–.61***–.47***–.61***BASC Internalizing–.44***–.43***BASC Externalizing–.42***–.41***BASC School Problems–.55***–.56***Waber, Gerber, Turcios, Wagner & Forbes, 2006
PlanWhat are the Executive Functions? How do we identify them? What is the brain basis anddevelopmental course? How do they manifest in clinicaldisorders? How do we intervene?
Model of Executive FunctionIntervention KnowledgeBase Settings ToolKit Delivery System
Knowledge Base OperationalDefinitions Clinical Manifestations Ways to Recognize/ AssessTask: Build EF expertise
Settings Home School Community(Job, peers)Task: Define the structure
Tool Kit TargetedFunctional Domains Strategies Scripts/ RoutinesTask: Develop broad flexibletools
Delivery System “Key:Personnel: Mentor/coach/ co-conductor “With” not “for” External to internalTask: Promote independence
EF InterventionGeneral Principles Good Assessment:Define relevant EFdeficit, associated domain specific abilitiesor deficits, and task/situational demands Determine the developmental level of childand what are age appropriate expectationsfor EF.
EF InterventionGeneral Principles Teach goal-directedproblem-solvingprocess, within everyday meaningful routines, having real -world relevance andapplication, using key people (parents/ teachers/ peers)as models, “coaches ” (Co-conductor).
EF InterventionGeneral PrinciplesExternal to internal process External models of multi-step problemsolving routines External guidance to develop &implement everyday routines Practice application/ use of routines Fade external support to cueing internalgeneration & use of routines
EF InterventionGeneral PrinciplesExternal to internal process Internal control to generate & use specificproblem-solving routine Generalization to new situation, requiringsome external guidance Accumulate experience, examine conditionsfor selective use of various routines Feedback throughout (i.e., reward)
Interventions: General Principles must fit with child, environment, teacher, parents make rationale work for the teacher/parent involve teacher/parent in planning possiblesolutions measure success / failure
Structuring an EFintervention program Use of everyday routines (e.g., Goal -Plan-Do-Review) Support working memory via “hardcopy” of routine Allowing child to become increasinglymore active in formulating plans andreviewing their performance
Goal-Plan-Do-ReviewGOALWhat do I want to accomplish?PLANHow am I going to accomplish my goal?MATERIALS/ EQUIPMENT1.2.STEPS/ASSIGNMENTS1.2.PREDICTION: HOW WELL WILL I DO?Self rating1 2 3 4 5 6 7Other Rating 1 2 3 4 5 6 7How much will I get :Self ratingOther ratingWHAT WORKED?1.2.112233HOW DID I DO?4 5 6 7 84 5 6 7 8991010WHAT DIDN'T WORK1.2.WHAT WILL I TRY NEXT TIME?
References Anderson, V., & Jacobs, R. (2008). Executive Functions and the Frontal Lobes: ALifespan Perspective. Taylor & Francis, Inc. Barkley, R. (1997) ADHD and the Nature of Self -Control. New York: Guilford Press. Blair, C., Greenberg, M.T., & Zelazo, P.D. (Eds). (2005). Measurement of ExecutiveFunction in Early Childhood: A Special Issue of Developmental NeuropsychologyNeuropsychology.Lawrence Erlbaum Associates, Inc. Dawson, P., & Guare , R. (2003). Executive Skills in Children & Adolescents: A practicalguide to assessment and intervention.intervention. NY: Guilford Press. Pennington, B.F. & OzonoffOzonoff,,S. (1996) Executive functions and developmental psychopathology. Journal of ChildPsychology and Psychiatry, 37, 51 -87. Gioia , G. A., Isquith, P. K., & Guy, S. C. (2001). Assessment of Executive Function inChildren with Neurological Impairments.Impairments. In R. Simeonsson & S. Rosenthal (Eds(Eds).).Psychological and Developmental Assessment. NY: The Guilford P ress. Gioia , G.A. & Isquith, P.K. (2001) New perspectives on educating children with ADHD:Contributions of the executive functions Journal of Health Care Law & Policy, 5, 124163. Goldberg, E. (2000) The Executive Brain: Frontal Lobes and the CivilizedCivilized Mind. NewYork: Oxford. Lyon, G.R. & Krasnegor, N.A. (1996) Attention, Memory and Executive Function.Baltimore: Paul H. Brookes Publishing Co. Meltzer, L. (2007) Executive Function in Education: From Theory to Practice.Practice. NY:Guilford Press. Ylvisaker, M. & Feeney, T.J. (1998) Collaborative Brain Injury Intervention: PositiveEveryday Routines . San Diego: Singular Publishing Co.
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