pupils uppils ppuils ppuils uppils pupils puipls upipls piupls ipupls uippls iuppls ppiuls ppiuls pipuls ippuls pipuls ippuls upipls puipls uippls iuppls piupls ipupls puplis upplis ppulis ppulis upplis puplis pulpis uplpis plupis lpupis ulppis luppis ppluis ppluis plpuis lppuis plpuis lppuis uplpis pulpis ulppis luppis plupis lpupis puilps upilps piulps ipulps uiplps iuplps pulips uplips pluips lpuips ulpips lupips pilups iplups pliups lpiups ilpups lipups uilpps iulpps ulipps luipps ilupps liupps ppilus ppilus piplus ipplus piplus ipplus pplius pplius plpius lppius plpius lppius pilpus iplpus plipus lpipus ilppus lippus pilpus iplpus plipus lpipus ilppus lippus upilps puilps uiplps iuplps piulps ipulps uplips pulips ulpips lupips pluips lpuips uilpps iulpps ulipps luipps ilupps liupps pilups iplups pliups lpiups ilpups lipups pupisl uppisl ppuisl ppuisl uppisl pupisl puipsl upipsl piupsl ipupsl uippsl iuppsl ppiusl ppiusl pipusl ippusl pipusl ippusl upipsl puipsl uippsl iuppsl piupsl ipupsl pupsil uppsil ppusil ppusil uppsil pupsil puspil upspil psupil spupil usppil suppil ppsuil ppsuil pspuil sppuil pspuil sppuil upspil puspil usppil suppil psupil spupil puispl upispl piuspl ipuspl uipspl iupspl pusipl upsipl psuipl spuipl uspipl supipl pisupl ipsupl psiupl spiupl ispupl sipupl uisppl iusppl usippl suippl isuppl siuppl ppisul ppisul pipsul ippsul pipsul ippsul ppsiul ppsiul pspiul sppiul pspiul sppiul pispul ipspul psipul spipul isppul sippul pispul ipspul psipul spipul isppul sippul upispl puispl uipspl iupspl piuspl ipuspl upsipl pusipl uspipl supipl psuipl spuipl uisppl iusppl usippl suippl isuppl siuppl pisupl ipsupl psiupl spiupl ispupl sipupl puplsi upplsi ppulsi ppulsi upplsi puplsi pulpsi uplpsi plupsi lpupsi ulppsi luppsi pplusi pplusi plpusi lppusi plpusi lppusi uplpsi pulpsi ulppsi luppsi plupsi lpupsi pupsli uppsli ppusli ppusli uppsli pupsli puspli upspli psupli spupli usppli suppli ppsuli ppsuli pspuli sppuli pspuli sppuli upspli puspli usppli suppli psupli spupli pulspi uplspi pluspi lpuspi ulpspi lupspi puslpi upslpi psulpi spulpi usplpi suplpi plsupi lpsupi pslupi splupi lspupi slpupi ulsppi lusppi uslppi sulppi lsuppi sluppi pplsui pplsui plpsui lppsui plpsui lppsui ppslui ppslui psplui spplui psplui spplui plspui lpspui pslpui splpui lsppui slppui plspui lpspui pslpui splpui lsppui slppui uplspi pulspi ulpspi lupspi pluspi lpuspi upslpi puslpi usplpi suplpi psulpi spulpi ulsppi lusppi uslppi sulppi lsuppi sluppi plsupi lpsupi pslupi splupi lspupi slpupi puilsp upilsp piulsp ipulsp uiplsp iuplsp pulisp uplisp pluisp lpuisp ulpisp lupisp pilusp iplusp pliusp lpiusp ilpusp lipusp uilpsp iulpsp ulipsp luipsp ilupsp liupsp puislp upislp piuslp ipuslp uipslp iupslp pusilp upsilp psuilp spuilp uspilp supilp pisulp ipsulp psiulp spiulp ispulp sipulp uisplp iusplp usiplp suiplp isuplp siuplp pulsip uplsip plusip lpusip ulpsip lupsip puslip upslip psulip spulip usplip suplip plsuip lpsuip psluip spluip lspuip slpuip ulspip luspip uslpip sulpip lsupip slupip pilsup iplsup plisup lpisup ilpsup lipsup pislup ipslup psilup spilup isplup siplup plsiup lpsiup psliup spliup lspiup slpiup ilspup lispup islpup silpup lsipup slipup uilspp iulspp ulispp luispp iluspp liuspp uislpp iuslpp usilpp suilpp isulpp siulpp ulsipp lusipp uslipp sulipp lsuipp sluipp ilsupp lisupp islupp silupp lsiupp sliupp ppilsu ppilsu piplsu ipplsu piplsu ipplsu pplisu pplisu plpisu lppisu plpisu lppisu pilpsu iplpsu plipsu lpipsu ilppsu lippsu pilpsu iplpsu plipsu lpipsu ilppsu lippsu ppislu ppislu pipslu ippslu pipslu ippslu ppsilu ppsilu pspilu sppilu pspilu sppilu pisplu ipsplu psiplu spiplu ispplu sipplu pisplu ipsplu psiplu spiplu ispplu sipplu pplsiu pplsiu plpsiu lppsiu plpsiu lppsiu ppsliu ppsliu pspliu sppliu pspliu sppliu plspiu lpspiu pslpiu splpiu lsppiu slppiu plspiu lpspiu pslpiu splpiu lsppiu slppiu pilspu iplspu plispu lpispu ilpspu lipspu pislpu ipslpu psilpu spilpu isplpu siplpu plsipu lpsipu pslipu splipu lspipu slpipu ilsppu lisppu islppu silppu lsippu slippu pilspu iplspu plispu lpispu ilpspu lipspu pislpu ipslpu psilpu spilpu isplpu siplpu plsipu lpsipu pslipu splipu lspipu slpipu ilsppu lisppu islppu silppu lsippu slippu upilsp puilsp uiplsp iuplsp piulsp ipulsp uplisp pulisp ulpisp lupisp pluisp lpuisp uilpsp iulpsp ulipsp luipsp ilupsp liupsp pilusp iplusp pliusp lpiusp ilpusp lipusp upislp puislp uipslp iupslp piuslp ipuslp upsilp pusilp uspilp supilp psuilp spuilp uisplp iusplp usiplp suiplp isuplp siuplp pisulp ipsulp psiulp spiulp ispulp sipulp uplsip pulsip ulpsip lupsip plusip lpusip upslip puslip usplip suplip psulip spulip ulspip luspip uslpip sulpip lsupip slupip plsuip lpsuip psluip spluip lspuip slpuip uilspp iulspp ulispp luispp iluspp liuspp uislpp iuslpp usilpp suilpp isulpp siulpp ulsipp lusipp uslipp sulipp lsuipp sluipp ilsupp lisupp islupp silupp lsiupp sliupp pilsup iplsup plisup lpisup ilpsup lipsup pislup ipslup psilup spilup isplup siplup plsiup lpsiup psliup spliup lspiup slpiup ilspup lispup islpup silpup lsipup slipup
Note: these 'words' (valid or invalid) are all the permutations of the word pupils. These words are obtained by scrambling the letters in pupils.