diff --git a/src/pages/js/030-array.mdx b/src/pages/js/030-array.mdx
new file mode 100644
index 0000000..2f2c315
--- /dev/null
+++ b/src/pages/js/030-array.mdx
@@ -0,0 +1,12 @@
+---
+layout: "@/layouts/MarkdownLayout.astro"
+---
+
+import RenderFile from "@/components/RenderFile";
+import RenderHtml from "@/components/RenderHtml";
+
+export const title = "配列をまとめて処理する";
+
+# {title}
+
+## TOC
diff --git a/src/pages/js/040-if.mdx b/src/pages/js/040-if.mdx
new file mode 100644
index 0000000..ebabdcd
--- /dev/null
+++ b/src/pages/js/040-if.mdx
@@ -0,0 +1,12 @@
+---
+layout: "@/layouts/MarkdownLayout.astro"
+---
+
+import RenderFile from "@/components/RenderFile";
+import RenderHtml from "@/components/RenderHtml";
+
+export const title = "if文で条件分岐する";
+
+# {title}
+
+## TOC
diff --git a/src/pages/js/090-work.mdx b/src/pages/js/090-work.mdx
new file mode 100644
index 0000000..f48d60d
--- /dev/null
+++ b/src/pages/js/090-work.mdx
@@ -0,0 +1,13 @@
+---
+layout: "@/layouts/MarkdownLayout.astro"
+---
+
+import RenderFile from "@/components/RenderFile";
+import RenderHtml from "@/components/RenderHtml";
+
+export const title = "ワーク";
+
+# {title}
+
+## TOC
+