diff --git a/.vscode/settings.json b/.vscode/settings.json
new file mode 100644
index 00000000..eecbcdc2
--- /dev/null
+++ b/.vscode/settings.json
@@ -0,0 +1,8 @@
+{
+    "github.copilot.enable": {
+        "*": false,
+        "plaintext": false,
+        "markdown": false,
+        "scminput": false
+    }
+}
\ No newline at end of file
diff --git a/index.js b/index.js
index 0f4b28b4..5dc67046 100644
--- a/index.js
+++ b/index.js
@@ -1,17 +1,46 @@
 class SortedList {
-  constructor() {}
+  //      1) should have items and length properties #add(x)
+  constructor() {
+    this.items = [];
+    this.length = 0;
+  }
+//      2) should add a single value to SortedList
 
-  add(item) {}
-
-  get(pos) {}
-
-  max() {}
+  add(item) {
+    this.items.push(item);
+    this.items.sort((a,b) => a -b);
+    this.length = this.items.length;
+  }
+  get(pos) {
+  if (pos >= this.length) {
+    throw new Error("OutOfBounds");
+  }
+  return this.items[pos];
+}
 
-  min() {}
+  max() {
+  if (this.length === 0) {
+    throw new Error("EmptySortedList");
+  }
+  return this.items[this.length - 1];
+}
+  min() {
+  if (this.length === 0) {
+    throw new Error("EmptySortedList");
+  }
+  return this.items[0];
+}
 
-  sum() {}
+  sum() {
+  return this.items.reduce((acc, val) => acc + val, 0);
+}
 
-  avg() {}
+  avg() {
+  if (this.length === 0) {
+    throw new Error("EmptySortedList");
+  }
+  return this.sum() / this.length;
+}
 }
 
 module.exports = SortedList;
diff --git a/package.json b/package.json
index 3a5127ae..f5d8555d 100644
--- a/package.json
+++ b/package.json
@@ -19,5 +19,8 @@
     "intro"
   ],
   "author": "fer@ironhack.com",
-  "license": "MIT"
+  "license": "MIT",
+  "dependencies": {
+    "mocha": "^11.6.0"
+  }
 }