diff --git a/ui/src/views/classroom/RoomDetail.tsx b/ui/src/views/classroom/RoomDetail.tsx
index 067f6a5a..e11c6849 100644
--- a/ui/src/views/classroom/RoomDetail.tsx
+++ b/ui/src/views/classroom/RoomDetail.tsx
@@ -136,6 +136,8 @@ const RoomDetail: React.FC = () => {
     autoMuteNewParticipants: true,
   })
 
+  const hasTeacher = (list: ClassroomParticipantDto[]) => list.some((p) => p.isTeacher)
+
   const signalRServiceRef = useRef<SignalRService>()
   const webRTCServiceRef = useRef<WebRTCService>()
 
@@ -270,35 +272,9 @@ const RoomDetail: React.FC = () => {
 
           console.log(`Participant joined: ${name}, isTeacher: ${isTeacher}`)
 
-          if (webRTCServiceRef.current) {
-            if (!webRTCServiceRef.current.getPeerConnection(userId)) {
-              await webRTCServiceRef.current.createPeerConnection(userId)
-            }
-
-            // student → teacher
-            if (user.role === 'student' && isTeacher) {
-              const offer = await webRTCServiceRef.current.createOffer(userId)
-              await signalRServiceRef.current?.sendOffer(classSession.id, userId, offer)
-            }
-
-            // teacher → student
-            if (user.role === 'teacher' && !isTeacher) {
-              const offer = await webRTCServiceRef.current.createOffer(userId)
-              await signalRServiceRef.current?.sendOffer(classSession.id, userId, offer)
-            }
-
-            // teacher ↔ teacher
-            if (user.role === 'teacher' && isTeacher) {
-              if (user.id < userId) {
-                const offer = await webRTCServiceRef.current.createOffer(userId)
-                await signalRServiceRef.current?.sendOffer(classSession.id, userId, offer)
-              }
-            }
-          }
-
+          // Katılımcıyı state'e ekle
           setParticipants((prev) => {
-            const exists = prev.find((p) => p.id === userId)
-            if (exists) return prev
+            if (prev.find((p) => p.id === userId)) return prev
             return [
               ...prev,
               {
@@ -310,6 +286,23 @@ const RoomDetail: React.FC = () => {
               },
             ]
           })
+
+          // ✅ sadece öğretmen sınıfta ise offer başlasın
+          const teacherExists = hasTeacher(participants) || isTeacher
+          if (!teacherExists) {
+            console.log('Teacher yok, yeni join için offer başlatılmıyor.')
+            return
+          }
+
+          if (!webRTCServiceRef.current?.getPeerConnection(userId)) {
+            await webRTCServiceRef.current?.createPeerConnection(userId)
+          }
+
+          // Küçük id kuralı
+          if (user.id < userId) {
+            const offer = await webRTCServiceRef.current!.createOffer(userId)
+            await signalRServiceRef.current?.sendOffer(classSession.id, userId, offer)
+          }
         },
       )
 
@@ -319,52 +312,9 @@ const RoomDetail: React.FC = () => {
           for (const participant of existing) {
             if (participant.userId === user.id) continue
 
-            console.log(
-              `Existing participant: ${participant.userName}, isTeacher: ${participant.isTeacher}`,
-            )
-
-            if (webRTCServiceRef.current) {
-              if (!webRTCServiceRef.current.getPeerConnection(participant.userId)) {
-                await webRTCServiceRef.current.createPeerConnection(participant.userId)
-              }
-
-              // 🔑 Eğer ben öğrenci isem, öğretmen için offer gönder
-              if (user.role === 'student' && participant.isTeacher) {
-                const offer = await webRTCServiceRef.current.createOffer(participant.userId)
-                await signalRServiceRef.current?.sendOffer(
-                  classSession.id,
-                  participant.userId,
-                  offer,
-                )
-              }
-
-              // 🔑 Eğer ben öğretmensem, öğrenci için offer gönder
-              if (user.role === 'teacher' && !participant.isTeacher) {
-                const offer = await webRTCServiceRef.current.createOffer(participant.userId)
-                await signalRServiceRef.current?.sendOffer(
-                  classSession.id,
-                  participant.userId,
-                  offer,
-                )
-              }
-
-              // 🔑 Öğretmen ↔ Öğretmen
-              if (user.role === 'teacher' && participant.isTeacher) {
-                // id’si küçük olan offer göndersin
-                if (user.id < participant.userId) {
-                  const offer = await webRTCServiceRef.current.createOffer(participant.userId)
-                  await signalRServiceRef.current?.sendOffer(
-                    classSession.id,
-                    participant.userId,
-                    offer,
-                  )
-                }
-              }
-            }
-
+            // Katılımcıyı state'e ekle
             setParticipants((prev) => {
-              const exists = prev.find((p) => p.id === participant.userId)
-              if (exists) return prev
+              if (prev.find((p) => p.id === participant.userId)) return prev
               return [
                 ...prev,
                 {
@@ -377,6 +327,27 @@ const RoomDetail: React.FC = () => {
               ]
             })
           }
+
+          // ✅ sadece öğretmen varsa offer başlat
+          const teacherExists = existing.some((p) => p.isTeacher)
+          if (!teacherExists) {
+            console.log('Teacher yok, offer başlatılmıyor.')
+            return
+          }
+
+          for (const participant of existing) {
+            if (participant.userId === user.id) continue
+
+            if (!webRTCServiceRef.current?.getPeerConnection(participant.userId)) {
+              await webRTCServiceRef.current?.createPeerConnection(participant.userId)
+            }
+
+            // Küçük id'li offer göndersin (çift offer olmaması için)
+            if (user.id < participant.userId) {
+              const offer = await webRTCServiceRef.current!.createOffer(participant.userId)
+              await signalRServiceRef.current?.sendOffer(classSession.id, participant.userId, offer)
+            }
+          }
         },
       )