diff --git a/frontend/src/components/QuizTools.jsx b/frontend/src/components/QuizTools.jsx
index ea30376..675cf36 100644
--- a/frontend/src/components/QuizTools.jsx
+++ b/frontend/src/components/QuizTools.jsx
@@ -52,7 +52,8 @@ const labFields = [
   ['article_id', 'Article ID (optional deep link)', 12], ['article_section_id', 'Article section ID (optional)', 64],
 ]
 
-function LabValues() {
+/** Exported so the player can dock it beside a question instead of over it. */
+export function LabValues() {
   const { user } = useAuth()
   const isEducator = ['admin', 'moderator'].includes(user?.role)
   const [rows, setRows] = useState([])
diff --git a/frontend/src/pages/QuizPage.jsx b/frontend/src/pages/QuizPage.jsx
index 4380f71..2f192b7 100644
--- a/frontend/src/pages/QuizPage.jsx
+++ b/frontend/src/pages/QuizPage.jsx
@@ -15,7 +15,7 @@ import FeedbackForm from '../components/FeedbackForm'
 import ShareSession from '../components/ShareSession'
 import MoreMenu from '../components/MoreMenu'
 import '../components/Feedback.css'
-import QuizTools, { QuizDialog } from '../components/QuizTools'
+import QuizTools, { QuizDialog, LabValues } from '../components/QuizTools'
 import './QuizPlayer.css'
 
 //: Seconds left when the block says so. Long enough to finish the question in
@@ -476,6 +476,20 @@ export default function QuizPage() {
   const [activeReadSegment, setActiveReadSegment] = useState(null)
   const [manualHighlights, setManualHighlights] = useState({})
   const [tool, setTool] = useState(null)
+  // Labs sit beside the question rather than over it: a reference range is
+  // read while re-reading the case, and a dialog covers the thing it is for.
+  const [labsOpen, setLabsOpen] = useState(false)
+  // The rail is a sidebar, not furniture: on a long stem the question wants
+  // the width, and the list is still one press away. Remembered, because
+  // somebody who put it away meant it.
+  const [railOpen, setRailOpen] = useState(() => {
+    try { return localStorage.getItem('pedshub.quizRail') !== 'closed' } catch { return true }
+  })
+
+  useEffect(() => {
+    try { localStorage.setItem('pedshub.quizRail', railOpen ? 'open' : 'closed') }
+    catch { /* private browsing */ }
+  }, [railOpen])
   // Which of the per-question panels is open. One at a time: they sit in the
   // same place under the stem, and two at once would push the options off screen.
   const [panel, setPanel] = useState(null)
@@ -1359,15 +1373,10 @@ const timerStarted = timeLeft !== null
         onClick={() => safeNavigate(Math.max(0, currentIdx - 1))}
         disabled={currentIdx === 0}>← Prev</button>
 
-      {/* Only where the rail is not on screen. Beside a permanent list of
-          every question, a button that unfolds the same list is noise. */}
-      {!hasRail && (
-        <button className="quiz-nav-toggle btn btn-secondary btn-sm"
-          aria-label={`Question ${currentIdx + 1} of ${totalCount} — open the session`}
-          onClick={() => { setDrawerTab('questions'); setNavOpen(true) }}>
-          {currentIdx + 1} / {totalCount} ☰
-        </button>
-      )}
+      {/* The bar is three things: leave, back, on. The question count and the
+          list behind it live in the rail and, on a narrow screen, behind the
+          site's own menu button — repeating them here crowded the one row
+          that has to stay legible at the foot of every question. */}
 
       {isLast && !reviewing ? (
         // The end of the block. In an exam the dialog names how many are still
@@ -1691,8 +1700,16 @@ const timerStarted = timeLeft !== null
         </div>
       )}
 
-      {/* Two-column layout: content + desktop sidebar */}
-      <div className="quiz-layout">
+      {/* The question, with the rail on one side and the labs on the other —
+          both optional, and the question taking whatever they leave. */}
+      <div className={`quiz-layout${railOpen ? '' : ' is-rail-closed'}${labsOpen ? ' has-labs' : ''}`}>
+        {/* Rendered whenever the rail is away, and hidden by the same
+            breakpoint that hides the rail — the sidebar is a CSS decision, and
+            its handle has to be made the same way or the two disagree. */}
+        {!railOpen && (
+          <button type="button" className="quiz-rail-reopen" aria-label="Show the session questions"
+            onClick={() => setRailOpen(true)}>›</button>
+        )}
         {/* Main content */}
         <div style={{ flex: 1, minWidth: 0 }}>
           <div className="quiz-topbar">
@@ -1731,8 +1748,14 @@ const timerStarted = timeLeft !== null
             )}
             <div className="quiz-top-actions">
               <button type="button" title="Keyboard shortcuts" aria-label="Keyboard shortcuts" onClick={() => setTool('shortcuts')}>⌨ <span>Shortcuts</span></button>
-              <button type="button" title="Calculator" aria-label="Calculator" onClick={() => setTool('calculator')}>▦ <span>Calculator</span></button>
-              <button type="button" title="Lab values" aria-label="Lab values" onClick={() => setTool('labs')}>⚗ <span>Lab values</span></button>
+              {/* Both are the exam's. A study session has no clock to beat, and
+                  the labs are on the question's own bar where the case is. */}
+              {!isStudy && (
+                <>
+                  <button type="button" title="Calculator" aria-label="Calculator" onClick={() => setTool('calculator')}>▦ <span>Calculator</span></button>
+                  <button type="button" title="Lab values" aria-label="Lab values" onClick={() => setTool('labs')}>⚗ <span>Lab values</span></button>
+                </>
+              )}
               {/* An exam moves between items from the middle of this bar, and
                   ends the block from the bar at the foot of it. Repeating
                   either here is the same action under a second name. */}
@@ -1775,6 +1798,14 @@ const timerStarted = timeLeft !== null
                 />
               </div>
               <div className="quiz-actionbar" role="toolbar" aria-label="Question actions">
+                {/* Beside the tip rather than up in the toolbar: reference
+                    ranges are read against the case in front of you, and a
+                    control at the top of the screen is a different place from
+                    where the numbers are. */}
+                <button type="button" className={labsOpen ? 'is-on' : ''}
+                  aria-pressed={labsOpen} onClick={() => setLabsOpen(v => !v)}>
+                  ⚗ <span>Labs</span>
+                </button>
                 {current.attending_tip && (
                   <button type="button" className={panel === 'tip' ? 'is-on' : ''}
                     aria-pressed={panel === 'tip'}
@@ -2129,9 +2160,24 @@ const timerStarted = timeLeft !== null
 
         </div>
 
+        {labsOpen && (
+          <aside className="quiz-labs" aria-label="Lab values">
+            <div className="quiz-labs-head">
+              <strong>Lab values</strong>
+              <button type="button" aria-label="Close lab values"
+                onClick={() => setLabsOpen(false)}>✕</button>
+            </div>
+            <div className="quiz-labs-body"><LabValues /></div>
+          </aside>
+        )}
+
         {/* Desktop rail — numbers with an excerpt, as in a Qbank session */}
         <div className="quiz-sidebar quiz-rail">
-          <div className="quiz-rail-head">Session questions</div>
+          <div className="quiz-rail-head">
+            <span>Session questions</span>
+            <button type="button" className="quiz-rail-hide" aria-label="Hide the session questions"
+              onClick={() => setRailOpen(false)}>‹</button>
+          </div>
           <div className="quiz-rail-list">
             {questions.map((q, i) => <QuestionRailItem key={q.id} q={q} i={i} />)}
           </div>
diff --git a/frontend/src/pages/QuizPage.test.jsx b/frontend/src/pages/QuizPage.test.jsx
index 491f476..6da6e1f 100644
--- a/frontend/src/pages/QuizPage.test.jsx
+++ b/frontend/src/pages/QuizPage.test.jsx
@@ -504,7 +504,9 @@ describe('quiz player', () => {
   })
 
   it('offers a functional calculator without hijacking input shortcuts', async () => {
-    await begin()
+    // The exam's. A study session has no clock to beat and no arithmetic to
+    // do under one, so the toolbar it sat in is the exam's too.
+    await begin(false)
     await userEvent.click(screen.getByRole('button', { name: /Calculator/ }))
     const dialog = screen.getByRole('dialog', { name: 'Calculator' })
     const input = within(dialog).getByLabelText('Calculation')
@@ -859,3 +861,30 @@ describe('quiz player', () => {
     expect(within(dialog).queryByRole('button', { name: 'Create a share link' })).toBeNull()
   })
 })
+
+it('keeps the exam\'s tools out of a study session', async () => {
+  await begin()
+  for (const gone of [/Calculator/, /Lab values/]) {
+    expect(screen.queryByRole('button', { name: gone })).not.toBeInTheDocument()
+  }
+  // Labs are on the question's own bar instead, where the case is.
+  const bar = screen.getByRole('toolbar', { name: 'Question actions' })
+  expect(within(bar).getByRole('button', { name: /Labs/ })).toBeInTheDocument()
+})
+
+it('puts the rail away and brings it back', async () => {
+  await begin()
+  expect(document.querySelector('.quiz-sidebar')).toBeInTheDocument()
+  await userEvent.click(screen.getByRole('button', { name: 'Hide the session questions' }))
+  // A long stem wants the width, and the list is still one press away.
+  expect(document.querySelector('.quiz-layout.is-rail-closed')).toBeInTheDocument()
+  await userEvent.click(screen.getByRole('button', { name: 'Show the session questions' }))
+  expect(document.querySelector('.quiz-layout.is-rail-closed')).toBeNull()
+})
+
+it('leaves three things at the foot: out, back, on', async () => {
+  await begin()
+  const bar = document.querySelector('.quiz-footbar')
+  const names = [...bar.querySelectorAll('button')].map(b => b.textContent.trim())
+  expect(names).toEqual(['Exit session', '← Prev', 'Skip →'])
+})
diff --git a/frontend/src/pages/QuizPlayer.css b/frontend/src/pages/QuizPlayer.css
index 9233f33..084ffad 100644
--- a/frontend/src/pages/QuizPlayer.css
+++ b/frontend/src/pages/QuizPlayer.css
@@ -524,3 +524,40 @@ body:has(.quiz-player.is-boxed) .site-footer { display: none; }
   border: 1px solid var(--correct-bd); border-radius: 9px;
 }
 .quiz-folder-new:disabled { opacity: 0.6; cursor: default; }
+
+/* ── The rail as a sidebar, and the labs as its opposite number ───────
+   Both are optional columns; the question takes whatever they leave. */
+.quiz-player .quiz-layout.is-rail-closed { grid-template-columns: minmax(0, 1fr); }
+.quiz-player .quiz-layout.is-rail-closed .quiz-sidebar { display: none; }
+.quiz-player .quiz-layout.has-labs { grid-template-columns: 260px minmax(0, 1fr) minmax(300px, 360px); }
+.quiz-player .quiz-layout.has-labs.is-rail-closed { grid-template-columns: minmax(0, 1fr) minmax(300px, 360px); }
+
+.quiz-rail-head { display: flex; align-items: center; justify-content: space-between; gap: 8px; }
+.quiz-rail-hide, .quiz-rail-reopen {
+  border: 1px solid var(--border); background: var(--card-bg); color: var(--text-muted);
+  border-radius: 50%; width: 24px; height: 24px; cursor: pointer; line-height: 1;
+  font-size: 0.9rem; flex-shrink: 0;
+}
+.quiz-rail-hide:hover, .quiz-rail-reopen:hover { color: var(--primary); border-color: var(--primary); }
+/* Sits where the rail was, so putting it back is where you last saw it. */
+.quiz-rail-reopen { align-self: start; margin-top: 4px; }
+
+.quiz-labs {
+  display: flex; flex-direction: column; min-height: 0;
+  border-left: 1px solid var(--border); background: var(--card-bg);
+}
+.quiz-labs-head {
+  display: flex; align-items: center; justify-content: space-between; gap: 8px;
+  padding: 10px 12px; border-bottom: 1px solid var(--border); flex: none;
+}
+.quiz-labs-head button { border: 0; background: none; cursor: pointer; color: var(--text-muted); font-size: 0.95rem; }
+.quiz-labs-body { flex: 1; min-height: 0; overflow-y: auto; padding: 10px 12px; }
+
+@media (max-width: 1150px) {
+  /* The rail is a drawer down here, so its handle has nothing to reopen. */
+  .quiz-rail-reopen { display: none; }
+  /* No room for a third column; the labs go back to being a dialog. */
+  .quiz-player .quiz-layout.has-labs,
+  .quiz-player .quiz-layout.has-labs.is-rail-closed { grid-template-columns: minmax(0, 1fr); }
+  .quiz-labs { display: none; }
+}