diff --git a/docs/openapi.yaml b/docs/openapi.yaml
index 17da479..1922ce2 100644
--- a/docs/openapi.yaml
+++ b/docs/openapi.yaml
@@ -91,7 +91,8 @@ paths:
           required: true
           schema:
             type: string
-          description: フォルダパス
+            example: School-ComputerScience-Python
+          description: フォルダパス ハイフン区切り
       responses:
         '200':
           description: OK
diff --git a/schema.sql b/schema.sql
index 668afbf..078c6c7 100644
--- a/schema.sql
+++ b/schema.sql
@@ -12,6 +12,7 @@ CREATE TABLE lectures (
     title TEXT NOT NULL,
     content TEXT NOT NULL,
     folder_id INT(11)
+    folder_path TEXT NOT NULL,
 );
 CREATE TABLE tags (
     id INT(11) NOT NULL PRIMARY KEY AUTO_INCREMENT,
@@ -27,6 +28,6 @@ CREATE TABLE tags_in_wiki (
 CREATE TABLE folders (
     id INT(11) NOT NULL PRIMARY KEY AUTO_INCREMENT,
     name TEXT NOT NULL,
-    parent_id INT(11),
+    parent_id INT(11),  -- 0 if root
     UNIQUE KEY (name, parent_id)
 );
\ No newline at end of file
diff --git a/src/handler/handler.go b/src/handler/handler.go
index 791a10b..faf8bda 100644
--- a/src/handler/handler.go
+++ b/src/handler/handler.go
@@ -1,7 +1,12 @@
 package handler
 
 import (
+	"database/sql"
+	"errors"
+	"log"
 	"net/http"
+	"strconv"
+	"strings"
 
 	"github.com/jmoiron/sqlx"
 	"github.com/labstack/echo"
@@ -15,6 +20,109 @@ func NewHandler(db *sqlx.DB) *Handler {
 	return &Handler{db: db}
 }
 
+// /ping
 func (h *Handler) PingHandler(c echo.Context) error {
 	return c.String(http.StatusOK, "pong")
 }
+
+// /lecture/byFolder/id/:folderId
+func (h *Handler) GetLectureByFolderIDHandler(c echo.Context) error {
+	folderID, err := strconv.Atoi(c.Param("folderId"))
+	if err != nil {
+		log.Printf("failed to convert folderId to int: %v", err)
+		return c.JSON(http.StatusBadRequest, err)
+	}
+
+	lectures := []LectureFromDB{}
+	err = h.db.Select(&lectures, "SELECT * FROM lectures WHERE folder_id = ?", folderID)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return c.JSON(http.StatusNotFound, err)
+		}
+		log.Printf("failed to get lectures: %v", err)
+		return c.JSON(http.StatusInternalServerError, err)
+	}
+
+	lecturesWithFolderPath := []Lecture{}
+	for _, lecture := range lectures {
+		lecturesWithFolderPath = append(lecturesWithFolderPath, Lecture{
+			ID:         lecture.ID,
+			Title:      lecture.Title,
+			Content:    lecture.Content,
+			FolderPath: lecture.FolderPath,
+		})
+	}
+
+	return c.JSON(http.StatusOK, lecturesWithFolderPath)
+}
+
+// /lecture/byFolder/path
+func (h *Handler) GetLectureByFolderPathHandler(c echo.Context) error {
+	folderPath := c.QueryParam("folderPath")
+
+	folderPath = "/" + strings.ReplaceAll(folderPath, "-", " /")
+	lectures := []LectureFromDB{}
+	err := h.db.Select(&lectures, "SELECT * FROM lectures WHERE folderpath = ?", folderPath)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return c.JSON(http.StatusNotFound, err)
+		}
+		log.Printf("failed to get lectures: %v", err)
+		return c.JSON(http.StatusInternalServerError, err)
+	}
+
+	lecturesWithFolderPath := []Lecture{}
+	for _, lecture := range lectures {
+		lecturesWithFolderPath = append(lecturesWithFolderPath, Lecture{
+			ID:         lecture.ID,
+			Title:      lecture.Title,
+			Content:    lecture.Content,
+			FolderPath: lecture.FolderPath,
+		})
+	}
+
+	return c.JSON(http.StatusOK, lecturesWithFolderPath)
+}
+
+// /lecture/folder/:folderId
+func (h *Handler) GetLectureChildFolderHandler(c echo.Context) error {
+	folderID, err := strconv.Atoi(c.Param("folderId"))
+	if err != nil {
+		log.Printf("failed to convert folderId to int: %v", err)
+		return c.JSON(http.StatusBadRequest, err)
+	}
+
+	files := []File{}
+	
+	childFolders := []FolderFromDB{}
+	err = h.db.Select(&childFolders, "SELECT * FROM folders WHERE parent_id = ?", folderID)
+	if err != nil && !errors.Is(err, sql.ErrNoRows) {
+		log.Printf("failed to get child folders: %v", err)
+		return c.JSON(http.StatusInternalServerError, err)
+	}
+
+	for _, folder := range childFolders {
+		files = append(files, File{
+			ID:       folder.ID,
+			Name:     folder.Name,
+			IsFolder: true,
+		})
+	}
+
+	childLectures := []LectureOnlyName{}
+	err = h.db.Select(&childLectures, "SELECT id, title FROM lectures WHERE folder_id = ?", folderID)
+	if err != nil && !errors.Is(err, sql.ErrNoRows) {
+		log.Printf("failed to get child lectures: %v", err)
+		return c.JSON(http.StatusInternalServerError, err)
+	}
+
+	for _, lecture := range childLectures {
+		files = append(files, File{
+			ID:       lecture.ID,
+			Name:     lecture.Title,
+			IsFolder: false,
+		})
+	}
+
+	return c.JSON(http.StatusOK, files)
+}
\ No newline at end of file
diff --git a/src/handler/model.go b/src/handler/model.go
new file mode 100644
index 0000000..607bb2c
--- /dev/null
+++ b/src/handler/model.go
@@ -0,0 +1,32 @@
+package handler
+
+type LectureFromDB struct {
+	ID         int    `db:"id"`
+	Title      string `db:"title"`
+	Content    string `db:"content"`
+	FolderID   int    `db:"folder_id"`
+	FolderPath string `db:"folderpath"`
+}
+
+type Lecture struct {
+	ID         int    `json:"id"`
+	Title      string `json:"title"`
+	Content    string `json:"content"`
+	FolderPath string `json:"folderpath"`
+}
+
+type FolderFromDB struct {
+	ID   int    `db:"id"`
+	Name string `db:"name"`
+}
+
+type File struct {
+	ID       int    `json:"id"`
+	Name     string `json:"name"`
+	IsFolder bool   `json:"isFolder"`
+}
+
+type LectureOnlyName struct {
+	ID    int    `db:"id"`
+	Title string `db:"title"`
+}