Classroom Attendance Wheel helps a teacher vary the order of row, table, group, or online attendance checks. It is a classroom prompt tool, not an official attendance record.
attendance orderclass check-ingroup roll callteacher spinner
Wheel of Names
Elimination: OFFAccumulation: OFFAuto-Spin: OFFFair Rotation: OFF
Add entries and spin the wheel.
(()=>{
const r=document.currentScript.closest(‘.wnx-spinner’);
if(!r||r.dataset.ready)return;
r.dataset.ready=’1′;
const $=s=>r.querySelector(s),$$=s=>[…r.querySelectorAll(s)];
const params=new URLSearchParams(location.search),cfg=document.querySelector(‘.wnx-config’);
const mode=cfg?.dataset.mode||r.dataset.mode||’standard’;
const title=cfg?.dataset.title||r.dataset.title||document.querySelector(‘.wn-page h1′)?.textContent||’Wheel of Names’;
const raw=params.get(‘wnitems’)||cfg?.dataset.items||r.dataset.items||’Alice~Bob~Charlie~David~Eve~Frank’;
const palettes=[
((cfg?.dataset.palette)||r.dataset.palette||”).split(‘,’).filter(Boolean),
[‘#6366f1′,’#8b5cf6′,’#ec4899′,’#f97316′,’#14b8a6′,’#3b82f6’],
[‘#ef476f’,’#f78c6b’,’#ffd166′,’#06d6a0′,’#118ab2′,’#7353ba’],
[‘#22c55e’,’#06b6d4′,’#3b82f6′,’#8b5cf6′,’#ec4899′,’#f59e0b’]
].filter(x=>x.length>2);
let colors=palettes[0];
let entries=raw.split(‘~’).map(v=>{try{return decodeURIComponent(v)}catch(e){return v}}).filter(Boolean).map(v=>{
const p=v.split(‘|’);
const weight=mode===’weighted’?Math.max(1,Number(p.pop())||1):1;
return{name:p.join(‘|’),weight,count:0,last:-999,image:”};
});
let angle=0,busy=false,history=[],undo=[],redo=[],spinNumber=0,lastReceipt=null,preSpin=[];
let backgroundImage=”,centerImage=”,backgroundOpacity=.45,centerRadius=76,pendingEntryImage=”,pendingEntryFilename=”;
const imageCache=new Map();
const canvas=$(‘.wnx-canvas’),ctx=canvas.getContext(‘2d’),spin=$(‘.wnx-spin’),result=$(‘.wnx-result’),list=$(‘.wnx-list’);
const elimination=$(‘.wnx-elimination’),accumulation=$(‘.wnx-accumulation’),auto=$(‘.wnx-auto’),winnerCount=$(‘.wnx-winner-count’),duration=$(‘.wnx-duration’);
const balance=$(‘.wnx-smart-balance’),cooldown=$(‘.wnx-smart-cooldown’);
$(‘.wnx-title’).textContent=title;
elimination.checked=mode===’norepeat’||params.get(‘wnremove’)===’1′;
winnerCount.value=mode===’multi’?Math.max(1,Number(cfg?.dataset.count||r.dataset.count)||3):1;
$(‘.wnx-multi-field’).classList.toggle(‘wnx-hidden’,mode!==’multi’);
const escapeHtml=s=>String(s).replace(/[&”‘]/g,m=>({‘&’:’&’,”:’>’,'”‘:’"’,”‘”:’'’}[m]));
const snapshot=()=>JSON.stringify(entries);
const save=()=>{undo.push(snapshot());if(undo.length>25)undo.shift();redo=[];};
const randomInt=n=>{if(n=limit);return a[0]%n;};
function getImage(src){
if(!src)return null;
if(imageCache.has(src))return imageCache.get(src);
const img=new Image();
img.onload=draw;
img.src=src;
imageCache.set(src,img);
return img;
}
function drawCover(img,x,y,w,h){
if(!img||!img.complete||!img.naturalWidth)return;
const scale=Math.max(w/img.naturalWidth,h/img.naturalHeight);
const dw=img.naturalWidth*scale,dh=img.naturalHeight*scale;
ctx.drawImage(img,x+(w-dw)/2,y+(h-dh)/2,dw,dh);
}
function readOptimizedImage(file,maxSize=1000){
return new Promise((resolve,reject)=>{
if(!file||!file.type.startsWith(‘image/’)){reject(new Error(‘Please choose an image file.’));return;}
const reader=new FileReader();
reader.onerror=()=>reject(new Error(‘The image could not be read.’));
reader.onload=()=>{
const img=new Image();
img.onerror=()=>reject(new Error(‘The image format is not supported.’));
img.onload=()=>{
const scale=Math.min(1,maxSize/Math.max(img.naturalWidth,img.naturalHeight));
const w=Math.max(1,Math.round(img.naturalWidth*scale)),h=Math.max(1,Math.round(img.naturalHeight*scale));
const temp=document.createElement(‘canvas’);temp.width=w;temp.height=h;
const t=temp.getContext(‘2d’);t.drawImage(img,0,0,w,h);
const type=file.type===’image/png’?’image/png’:’image/jpeg’;
resolve(temp.toDataURL(type,type===’image/jpeg’?.86:undefined));
};
img.src=String(reader.result||”);
};
reader.readAsDataURL(file);
});
}
const smartOn=()=>!elimination.checked&&(balance.checked||Number(cooldown.value)>0);
function eligibleEntries(){
let pool=[…entries];
if(!smartOn())return pool;
const cd=Number(cooldown.value);
if(cd>0){const cooled=pool.filter(e=>spinNumber-e.last>=cd);if(cooled.length)pool=cooled;}
if(balance.checked&&pool.length){const min=Math.min(…pool.map(e=>e.count));pool=pool.filter(e=>e.count===min);}
return pool.length?pool:[…entries];
}
function segments(){
const total=entries.reduce((s,e)=>s+e.weight,0)||1;
let used=0;
return entries.map(entry=>{const start=used/total*Math.PI*2;used+=entry.weight;return{entry,start,end:used/total*Math.PI*2};});
}
function draw(){
const size=900,center=450,radius=418,segs=segments(),allowed=new Set(eligibleEntries());
ctx.clearRect(0,0,size,size);
if(backgroundImage){
const img=getImage(backgroundImage);
ctx.save();ctx.beginPath();ctx.arc(center,center,radius,0,Math.PI*2);ctx.clip();ctx.globalAlpha=backgroundOpacity;drawCover(img,center-radius,center-radius,radius*2,radius*2);ctx.restore();
}
if(!segs.length){
ctx.beginPath();ctx.arc(center,center,radius,0,Math.PI*2);ctx.fillStyle=’#0b1628′;ctx.fill();ctx.strokeStyle=’rgba(129,140,248,.24)’;ctx.lineWidth=6;ctx.stroke();ctx.fillStyle=’#94a3b8′;ctx.font=’800 34px system-ui’;ctx.textAlign=’center’;ctx.fillText(‘Add entries’,center,center);return;
}
segs.forEach((seg,index)=>{
const dim=smartOn()&&!allowed.has(seg.entry);
const start=seg.start+angle,end=seg.end+angle;
ctx.save();
ctx.globalAlpha=dim?.2:1;
ctx.beginPath();ctx.moveTo(center,center);ctx.arc(center,center,radius,start,end);ctx.closePath();
if(seg.entry.image){
ctx.save();ctx.clip();drawCover(getImage(seg.entry.image),center-radius,center-radius,radius*2,radius*2);ctx.restore();
ctx.globalAlpha=dim?.12:.22;ctx.fillStyle=colors[index%colors.length];ctx.fill();ctx.globalAlpha=dim?.2:1;
}else{
ctx.fillStyle=colors[index%colors.length];
if(backgroundImage)ctx.globalAlpha=dim?.14:.72;
ctx.fill();ctx.globalAlpha=dim?.2:1;
}
ctx.strokeStyle=’rgba(255,255,255,.82)’;ctx.lineWidth=5;ctx.stroke();
const mid=(seg.start+seg.end)/2+angle;
ctx.translate(center,center);ctx.rotate(mid);ctx.textAlign=’right’;ctx.fillStyle=’#fff’;ctx.shadowColor=’rgba(0,0,0,.55)’;ctx.shadowBlur=8;
ctx.font=`850 ${Math.max(18,Math.min(33,350/entries.length+16))}px system-ui`;
const label=seg.entry.name.length>22?seg.entry.name.slice(0,20)+’…’:seg.entry.name;
ctx.fillText(label,radius-34,10);ctx.restore();
});
ctx.save();ctx.beginPath();ctx.arc(center,center,centerRadius,0,Math.PI*2);ctx.clip();
if(centerImage){drawCover(getImage(centerImage),center-centerRadius,center-centerRadius,centerRadius*2,centerRadius*2);}else{ctx.fillStyle=’#0b1628′;ctx.fillRect(center-centerRadius,center-centerRadius,centerRadius*2,centerRadius*2);}
ctx.restore();ctx.beginPath();ctx.arc(center,center,centerRadius,0,Math.PI*2);ctx.strokeStyle=’rgba(255,255,255,.24)’;ctx.lineWidth=10;ctx.stroke();
}
function updateBadges(){
[[ $(‘.wnx-badge-elimination’),elimination,’Elimination’],[$(‘.wnx-badge-accumulation’),accumulation,’Accumulation’],[$(‘.wnx-badge-auto’),auto,’Auto-Spin’],[$(‘.wnx-badge-smart’),{checked:smartOn()},’Fair Rotation’]].forEach(([el,input,label])=>{el.textContent=`${label}: ${input.checked?’ON’:’OFF’}`;el.classList.toggle(‘is-on’,input.checked);});
}
function balanceScore(){
if(!entries.length)return 100;
const total=entries.reduce((s,e)=>s+e.count,0),mean=total/entries.length;
if(!mean)return 100;
const deviation=entries.reduce((s,e)=>s+Math.abs(e.count-mean),0)/entries.length;
return Math.max(0,Math.round(100-deviation/mean*100));
}
function updateDashboard(){
$(‘.wnx-balance-score’).textContent=balanceScore()+’%’;$(‘.wnx-smart-spins’).textContent=String(spinNumber);
$(‘.wnx-smart-counts’).innerHTML=[…entries].sort((a,b)=>a.count-b.count||a.name.localeCompare(b.name)).map(e=>`
${escapeHtml(e.name)}${e.count}
`).join(”)||’
No entries yet.
‘;
const status=$(‘.wnx-smart-status’);
if(elimination.checked&&(balance.checked||Number(cooldown.value)>0))status.textContent=’Smart Fair Rotation is paused while Elimination mode is active.’;
else if(!smartOn())status.textContent=’Pure random mode is active.’;
else{const parts=[];if(balance.checked)parts.push(‘least-selected priority’);if(Number(cooldown.value)>0)parts.push(`${cooldown.value}-spin cooldown`);status.textContent=`Smart mode active: ${parts.join(‘ + ‘)}. Dimmed slices are temporarily ineligible.`;}
}
function render(){
list.innerHTML=entries.map((entry,index)=>`
Classroom Attendance Wheel is a free browser-based classroom attendance and turn-order randomizer that can call each current student once. Edit the sample entries, confirm the eligible list, choose the mode that matches the activity, and spin for a visible random result. Use the current class list, protect student information, respect approved accommodations, and keep official attendance records in the school system rather than in the wheel.
Keep official attendance separate
The wheel can choose which prepared section is checked next, but it should not replace the school register or approved attendance system. Do not type health information, contact details, identification numbers, or other sensitive student data into a public display.
Useful for visible groups
Use table labels, rows, class sections, or remote groups so the wheel supports the check-in without exposing a full personal roster.
Not an attendance database
Record attendance in the institution’s authorized system and follow local procedures for late arrivals and absences.
A simple classroom check-in flow
Prepare neutral labels
Add group or seating labels that students can identify quickly.
Spin through every group
No-repeat mode removes each checked group until all sections are complete.
Complete the official record
Transfer confirmed information only through the approved attendance process.