BUILDING WITH NUMBERS

MODULE 4:INVESTIGATION 2

TimersandStopwatches

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ACTIVITY 4.2.1

BuildaStopwatch

MODULE 4:INVESTIGATION 2Activity4.2.1– BuildaStopwatch

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Openproject4-Stopwatch - ifonline Saveasacopyandaddyourname- ifoffline Saveasandaddyourname

Exploretheproject.Lookatthesetupscriptaswellasthecostumes ofthe1secs sprite.

Duplicate the1secsspriteandrenameto10secs.Duplicate twomoretimesandrenameto1minsand10mins.Updateallsetupscripts.

MODULE 4:INVESTIGATION 2Activity4.2.1– BuildaStopwatch

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MODULE 4:INVESTIGATION 2Activity4.2.1– BuildaStopwatch

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u Timeisrepresentedusingthesamedigitcostumesasthepreviousinvestigation,howevertheplacevaluesaredifferent.Whatisthesameandwhatisdifferentbetweenthetwomodels?

u Whathappenswhen1secs getsto0again?Doesitnudge10secs?

Forthe1secsspritebuildabehaviour:wait1secsthendisplaynextcostume.Dothisforever.Addthehatblock:

Note: 1secs willbetheonlyspritewithwhenthisspriteclicked,otherswillreactonlytobroadcasting.

Likeearlier,makethe1secssprite‘nudge’10secs spritewhenappropriate,i.e.whenitreachesitslastcostume.

MODULE 4:INVESTIGATION 2Activity4.2.1– BuildaStopwatch

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10secs shouldreactbynextcostume.Thissimplescript,however,mustbeextendedaswell:whenappropriate10secswillbroadcastitsmessage– add1min.

1minsspritewillreact.Completeanddebugthescriptsofallfourdigits.

MODULE 4:INVESTIGATION 2Activity4.2.1– BuildaStopwatch

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u Whathappens1secondafter00:59?

u Whichcostumesdoes10secs actuallyneed?

u Haveyoudeletedorskippedtheothercostumes?

MODULE 4:INVESTIGATION 2Activity4.2.1– BuildaStopwatch

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Areyourscriptssimilartothebelow?Discussanyalternativesolutions.

[Extension]Measuretheaccuracyofthestopwatchanddiscuss.

[Extension]Explorehowtomakethetimepassmorequicklyorslowly.

[Extension]Extendyourstopwatchtoshowamoreaccuratetimebyshowingtenthsofseconds.

MODULE 4:INVESTIGATION 2Activity4.2.1– Extension:BuildaStopwatch

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u Doesitworkproperly?Ifnot,whydoyouthinkthatis?

u Howwouldthemodelworkifyouextendedittoincludehours?Howmanycostumeswouldeachspriteneed?

ACTIVITY 4.2.2

Unplugged:NudgeNudge GetGet

MODULE 4:INVESTIGATION 2Activity4.2.2– Unplugged:NudgeNudge GetGet

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Threepupilsstandatthefront(hundreds,tensandones).

Settheinitialnumberbygivingeachpupilaflipbook–pupilsatthefrontmustnotseeeachothers’flipbooks,everyoneelsemustchecktheydon’tcheat!

Agreeatargetnumber– teacherexplainstherules.

Playthegame!

MODULE 4:INVESTIGATION 2Activity4.2.2– Unplugged:NudgeNudge GetGet

hundreds tens ones

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MODULE 4:INVESTIGATION 2Activity4.2.2– Unplugged:NudgeNudge GetGet

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u Canyouexplainwhatyouhaveseenduringthisactivity?

u Whatisthesmallest(orthelargest)numberofrollsofthedietogetfrom111to90.Howcanwecalculatethis?

ACTIVITY 4.2.3

CountdownConundrum

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

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Openproject4-Timer - ifonline Saveasacopyandaddyourname- ifoffline Saveasandaddyourname

Exploretheproject. Lookatthescriptsofeachofthesprites1secs,10secs and1mins.

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

u Howcanwesettheinitialtime?E.g.3:25?Or1:58?

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Settheinitialtimee.g.to3minutes25seconds...…bychangingthevaluesoftheswitchcostumeto...blocksinthesetupscripts.

Forthe1secsspritemakeanewblockcalledpreviouscostume todecreaseitsvalue(i.e.costume)byone.

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

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Exploreandcomparebyclicking:

For1secsspritebuildascript:whenthisspriteclicked itwillwait1secsthendisplayitspreviouscostumeagainandagaininaforever loop.

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

u Whatshouldhappenwhenthe1secs spritereaches0andwantstodecreaseby1?

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For1secs:beforeitgoestopreviouscostume,itchecksifithasnotalreadyreached0andifithasitbroadcastsamessageget10secs.Onlythenitdecreasesitsvalue.

Copythepreviouscostumedefinitionintothe10secsspritebydraggingitfrom1secs.

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

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u Whowillreacttothemessageget10secs?How?

Forthe10secsspritebuildascriptthatwilldecreaseitsnumber(i.e.costume#)by1whenitreceivesget10secsmessage.

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

u Whatshouldhappenwhenthe10secs spritereaches0?Whenexactlyshoulditask1minstoget‘more’?Whatshould10secs‘flip’itscostumeto?

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Extendthescriptof10secs:beforeitgoestopreviouscostume itmustcheckwhetheritneedstogetextrafrom1mins– bybroadcastingget1min.

Buildcorrectreactionof1mins.

Debugallscripts,experimentwith‘quicker’or‘slower’timepassing.

MODULE 4:INVESTIGATION 2Activity4.2.3– CountdownConundrum

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u Will1mins needthedefinitionofpreviouscostume aswell?Whathappensafter2:01?Andthenextsecond?

[Extension]Whathappenswhenyourtimergetsto0:00(or00:00ifyouadded10mins)?

Thinkofastrategy(algorithm)tomakeyourtimerstopatthatpoint.Youmayneedtheblock:

Youmayalsoneedtoreplace‘simplegetting’bymore‘safegetting’– whenaspritebroadcastsamessage,itmaywaittoensurethereactionissuccessfullycompleted.Forthis,usethesecondtypeofbroadcastblock:

MODULE 4:INVESTIGATION 2Activity4.2.3– [Extension]CountdownConundrum

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EXTENSION ACTIVITY 4.2.4

DizzyDials

MODULE 4:INVESTIGATION 2Ext.Activity4.2.4– DizzyDials

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Openproject4-Dials - ifonline Saveasacopyandaddyourname- ifoffline Saveasandaddyourname

Exploretheproject. Lookatthescriptsofeachofthesprites1secs,10secs,1mins,secondshand andminuteshand.

Runtheprojectbyclickingthegreenflagthenclicking1secs.

MODULE 4:INVESTIGATION 2Ext.Activity4.2.4– DizzyDials

u Whatnewspritesdoyouhave?

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Explorethesecondshandsprite.Notepointindirection0blockinitssetupscript.Exploreseveralsimilarblockslike:

Wewantsecondshandtofollowbroadcastsfrom1secs.Inthe1secsspriteaddthebehaviourtobroadcast themessagetick everysecond,i.e.eachtimethecostume#increasesby1.

MODULE 4:INVESTIGATION 2Ext.Activity4.2.4– DizzyDials

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u Howshouldthesecondhandreact?

Forthesecondshand spritebuildascripttoturnright…degreeseachtimeitreceivesthemessagetick.

Nowexploretheminuteshand.Whydon’tweseeit?Makeitvisible.Canitturnaswell? Explore.

MODULE 4:INVESTIGATION 2Ext.Activity4.2.4– DizzyDials

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u Whatangleshouldthesecondshandspriteturnafteronesecondhaspassed?Why?

Intheminuteshand spritebuildascripttoturnright…degreeseachtimeitreceivesthemessageadd1min – itisalreadybeingbroadcastby10secs:

Testoutyourdials!

MODULE 4:INVESTIGATION 2Ext.Activity4.2.4– DizzyDials

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u Whenshouldtheminutehandspriteturn?Howcanwetellittoturnatthatpoint?

u Whatangleshouldtheminuteshandspriteturnafteroneminutehaspassed?Why?

[Advancedextension]Explorethegotofront blocktoensuretheminuteshandisinfrontofthesecondshand.

[Advancedextension]Edittheprojectsothatwhenthesecondhandturnsitgraduallyfillsthedialwithcolour.

Hint: Secondshandisnormalspriteandassuchitcanalsodraw.Setitspensizeandcolourproperlyandmakethespritedrawalinethenmovebackandonlythenturn.Experimentandexplore.

MODULE 4:INVESTIGATION 2Ext.Activity4.2.4– DizzyDials

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MyInvestigation2 checklist:

Ibuiltastopwatchthatcountsupinsecondsandminutes.

[Extension]Ichangedthespeedofmystopwatch.

[Extension]Iaddedtenthsofsecondstomystopwatch.

Ibuiltatimerthatcountsdowninsecondsandminutes.

Ibuiltanewblockpreviouscostume thatswitchesthesprite’scostumetothepreviousone.

[Extension]Istoppedmytimerat0:00.

[Extension]Ibuiltananalogueclockthatmirrorsthesametimeasmydigitaldisplay.

MODULE 4:INVESTIGATION 2

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isusedtostopallrunningscriptsinaprojectatthesametime

MODULE 4INVESTIGATION 2:KeyVocabulary

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