diff --git a/src/main/java/org/olat/modules/curriculum/manager/CurriculumServiceImpl.java b/src/main/java/org/olat/modules/curriculum/manager/CurriculumServiceImpl.java
index 96a144001154811f3d8f1384a8cdd00f051c1341..70a97606b93fab7d85977dbcc94c7eb2d8f1a5e9 100644
--- a/src/main/java/org/olat/modules/curriculum/manager/CurriculumServiceImpl.java
+++ b/src/main/java/org/olat/modules/curriculum/manager/CurriculumServiceImpl.java
@@ -78,6 +78,7 @@ import org.olat.modules.curriculum.model.CurriculumMember;
 import org.olat.modules.curriculum.model.CurriculumRefImpl;
 import org.olat.modules.curriculum.model.CurriculumSearchParameters;
 import org.olat.modules.curriculum.model.SearchMemberParameters;
+import org.olat.modules.lecture.manager.LectureBlockToGroupDAO;
 import org.olat.modules.taxonomy.TaxonomyLevel;
 import org.olat.modules.taxonomy.TaxonomyLevelRef;
 import org.olat.repository.RepositoryEntry;
@@ -111,6 +112,8 @@ public class CurriculumServiceImpl implements CurriculumService, OrganisationDat
 	@Autowired
 	private CurriculumMemberQueries memberQueries;
 	@Autowired
+	private LectureBlockToGroupDAO lectureBlockToGroupDao;
+	@Autowired
 	private RepositoryEntryMyCourseQueries myCourseQueries;
 	@Autowired
 	private RepositoryEntryDAO repositoryEntryDao;
@@ -390,6 +393,8 @@ public class CurriculumServiceImpl implements CurriculumService, OrganisationDat
 		}
 		// remove relations to taxonomy
 		curriculumElementToTaxonomyLevelDao.deleteRelation(reloadedElement);
+		// remove relations to lecture blocks
+		lectureBlockToGroupDao.deleteLectureBlockToGroup(reloadedElement.getGroup());
 		
 		boolean delete = true;
 		Map<String,CurriculumDataDeletable> deleteDelegates = CoreSpringFactory.getBeansOfType(CurriculumDataDeletable.class);
diff --git a/src/main/java/org/olat/modules/lecture/model/LectureBlockToGroupImpl.java b/src/main/java/org/olat/modules/lecture/model/LectureBlockToGroupImpl.java
index 18dcb05640fd13325f24e936dbfc64efe0fbd20e..0afba8be6fce367dfcaefdd1a0ce355c668b2acb 100644
--- a/src/main/java/org/olat/modules/lecture/model/LectureBlockToGroupImpl.java
+++ b/src/main/java/org/olat/modules/lecture/model/LectureBlockToGroupImpl.java
@@ -72,6 +72,7 @@ public class LectureBlockToGroupImpl implements Persistable, LectureBlockToGroup
 		this.lectureBlock = lectureBlock;
 	}
 
+	@Override
 	public Group getGroup() {
 		return group;
 	}