chore(curriculum): rm vids from classes & recursion lectures (#61573)

curriculum/challenges/english/25-front-end-development/lecture-understanding-how-to-work-with-classes-in-javascript/6733affc29df1304e2c97e88.md

@@ -1,19 +1,12 @@
 ---
 id: 6733affc29df1304e2c97e88
 title: What Are Classes, and How Do They Work in JavaScript?
-challengeType: 11
-videoId: Ap99e6plM10
+challengeType: 19
 dashedName: what-are-classes-and-how-do-they-work-in-javascript
 ---
 
 # --description--
 
-Watch the video or read the transcript and answer the questions below.
-
-# --transcript--
-
-What are classes, and how do they work in JavaScript?
-
 Let's learn about classes in JavaScript.
 
 In modern JavaScript, classes are like blueprints that you can define in code for creating multiple objects of the same kind.

curriculum/challenges/english/25-front-end-development/lecture-understanding-how-to-work-with-classes-in-javascript/673403ca2bb16658309e3632.md

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 ---
 id: 673403ca2bb16658309e3632
 title: How Does the This Keyword Work?
-challengeType: 11
-videoId: Tt1v6kLAdMo
+challengeType: 19
 dashedName: how-does-the-this-keyword-work
 ---
 
 # --description--
 
-Watch the video or read the transcript and answer the questions below.
-
-# --transcript--
-
-How does the `this` keyword work?
-
 Let's learn about the `this` keyword. You learned that classes are like blueprints that you can use to create objects.
 
 These blueprints need a general way to refer to the specific object that is being created, accessed, or modified within the code. That's exactly what the `this` keyword is used for. It refers to the context where the code is supposed to run. If you use it within a method, the value of `this` will be a reference to the object associated to that method. This way, you can access the properties and methods of the object within the class and reuse the method on different objects.

curriculum/challenges/english/25-front-end-development/lecture-understanding-how-to-work-with-classes-in-javascript/673403d2aa52d8586a14a269.md

@@ -1,19 +1,12 @@
 ---
 id: 673403d2aa52d8586a14a269
 title: What Is Class Inheritance, and How Does It Work?
-challengeType: 11
-videoId: DNO-xTd5D70
+challengeType: 19
 dashedName: what-is-class-inheritance-and-how-does-it-work
 ---
 
 # --description--
 
-Watch the video or read the transcript and answer the questions below.
-
-# --transcript--
-
-What is class inheritance, and how does it work?
-
 Let's learn about inheritance and how it works in JavaScript.
 
 In programming, inheritance allows you to define classes that inherit properties and methods from other classes.

curriculum/challenges/english/25-front-end-development/lecture-understanding-how-to-work-with-classes-in-javascript/673403dbf5c9835898632c84.md

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 ---
 id: 673403dbf5c9835898632c84
 title: What Are Static Properties and Methods in Classes?
-challengeType: 11
-videoId: xDIqlqh6_EU
+challengeType: 19
 dashedName: what-are-static-properties-and-methods-in-classes
 ---
 
 # --description--
 
-Watch the video or read the transcript and answer the questions below.
-
-# --transcript--
-
-What are static properties and methods in classes?
-
 Let's learn about static properties and methods.
 
 Static properties and methods belong to the class itself, not to the individual instances of the class. You can access them directly on the class name without creating an instance of the class. They are defined within classes to encapsulate related functionality.

curriculum/challenges/english/25-front-end-development/lecture-understanding-recursion-and-the-call-stack/6733b02d1e556005a544c5e3.md

@@ -1,19 +1,12 @@
 ---
 id: 6733b02d1e556005a544c5e3
 title: What Is Recursion, and How Does It Work?
-challengeType: 11
-videoId: u2Z7fAAzbYc
+challengeType: 19
 dashedName: what-is-recursion-and-how-does-it-work
 ---
 
 # --description--
 
-Watch the video or read the transcript and answer the questions below.
-
-# --transcript--
-
-What is recursion, and how does it work?
-
 Let's learn how recursion works in JavaScript.
 
 Recursion is a complicated feature that allows you to call a function repeatedly until a base-case is reached. Unlike a traditional loop, recursion allows you to handle something with an unknown depth, such as deeply nested objects/arrays, or a file tree. But you can also use it for more basic tasks, such as counting down from a given number.