Scratch是目前非常流行的少儿编程语言。本书基于Scratch 3.5版本，系统、全面、细致地讲解了Scratch的编程技巧，旨在培养孩子的逻辑思维和计算思维能力。

本书包括两大部分：第一部分是Scratch快速入门，分为12章，介绍了Scratch的各个方面，并细致地讲解了项目制作过程；第二部分是计算思维及项目实例，首先通过实例讲解计算思维的4个组成部分以及如何提高计算思维能力，然后通过4个有趣的综合实例（“打地鼠”游戏、四则运算测验、画彩虹系列、冒泡排序法）讲解如何基于计算思维进行项目开发与制作。

本书适合6~16岁的少儿阅读，对于6~8岁的少儿，建议采用亲子阅读的方式；对于9岁及以上的少儿，则完全可以自学。本书还可用作学校或培训机构的Scratch课程教材。

前 言

当你翻开这本书时，无论你是对信息技术感兴趣的孩子，还是关心少儿编程的家长，抑或是学校或培训机构的老师，我们都可以负责任地说：你选对了！对于6~8岁的少儿，本书适合亲子共读；而对于9岁及以上的少儿，本书则完全可用于自学。

近几年，计算机的应用越来越普及，编程也变得越来越重要。小到智能手机，大到太空探索，都离不开编程。随着信息技术迅速走进我们的日常生活，编程教育已经走进了中小学的课堂。少儿编程已经成为一个热门词汇，在百度上搜索“少儿编程”，竟然有近两千万条搜索结果。

那么，什么是编程呢？

编程就是用程序语言编写计算机能够理解的代码，让它按照我们写的命令（也称为指令）序列执行，以完成我们想要它完成的任务。但是，当面对具体的任务时，如何知道该编写怎样的代码呢？这就需要我们先进行问题分析和求解，找出解决问题的方法和步骤（称为算法），然后再根据算法编写程序。

可见，编程并不单指写代码，实际上，学习编程更重要的是学习分析问题和解决问题的方法，它能提高孩子的逻辑思维和计算思维能力。反过来，我们也要基于计算思维来学习编程，计算思维是一种求解问题的方式，它有4个主要组成部分：分解、模式识别、抽象化、算法开发。计算思维对于提高少儿利用现代技术分析问题和解决问题的能力有不可估量的启蒙作用。基于计算思维来讲解编程正是本书的重要特色之一。

Scratch 是专门为6~16岁少儿设计的编程语言和软件，可以免费下载使用。利用它，孩子们可以很容易地创作出可互动的故事、游戏、动画、音乐和艺术作品等。

Scratch是图形化编程软件，孩子们通过用鼠标拖曳色彩丰富的积木块，就可以像搭积木那样轻松进行编程。这使得孩子们不必学习复杂的编程语法，而是专注于实现自己的创意和想法，增加了编程的互动性和趣味性。本书是基于Scratch 3.5编写的。本书采用了丰富的、富有趣味性的实例，文字简洁流畅，图文并茂，操作步骤详细、直观，非常有利于孩子们的理解，具有很好的可读性，这是本书的第二大特色。 

另外，本书配有详细的视频教程（扫描书中相应的二维码即可观看），并采用动画形式进行

讲解，寓教于乐，这是本书的第三大特色。

本书第1章～第13章以及附录由张硕编写，第14章～第17章由张晨曦编写。书中所有实例的代码和素材均可在线获得，请扫描本书封底的“本书资源”二维码下载。

目? 录

第一部分? Scratch快速入门

第1章  初识Scratch····················2

1.1? 什么是编程··············································· 2

1.2? Scratch简介·············································· 3

1.3? Scratch的下载和安装······························· 4

1.3.1  计算机操作基础········································4

1.3.2  Scratch的下载···········································6

1.3.3  Scratch的安装···········································7

1.3.4  Scratch的启动···········································8

1.4? Scratch的编程界面··································· 9

1.4.1  积木区·····························10

1.4.2  代码区·····························11

1.4.3  角色区·····························13

1.4.4  舞台区·····························13

1.4.5  背景区·····························13

1.4.6  标签栏·····························14

1.4.7  菜单栏·····························15

1.4.8  按钮·································17

1.5? 动手做一做··············································17

第2章  角色·······························20

2.1? 什么是角色·············································20

2.2? 角色列表·························21

2.3? 添加、删除和复制角色·························22

2.3.1  添加角色··························22

2.3.2  删除角色··························23

2.3.3  复制角色··························23

2.4? 状态信息························23

2.5? 造型······························· 24

2.6? 配音································27

第3章  让角色“活”起来································29

3.1? 移动································29

3.1.1  舞台的直角坐标系···································29

3.1.2  用于移动角色的积木·······························31

3.1.3  动手做一做··············································33

3.1.4  位置监视器··············································35

3.2? 旋转······························· 35

3.2.1  角色的方向··············································35

3.2.2  用于旋转角色的积木·······························36

3.2.3  方向监视器··············································37

3.2.4  动手做一做··············································38

3.3? 碰到边缘就反弹·····································38

3.4? 变换造型························39

3.4.1  动画片的原理··········································39

3.4.2  动手做一做··············································40

3.5? 综合实例：海底世界······························41

3.5.1  任务描述··························41

3.5.2  构思和设计··············································41

3.5.3  编程实现··························42

第4章  外观：看我变变变································45

4.1? “说”和“思考”··································45

4.1.1  “说”和“思考”积木···························45

4.1.2  动手做一做··············································46

4.2? 改变大小·························47

4.2.1  改变大小的积木······································47

4.2.2  动手做一做··············································48

4.3? 改变背景························50

4.3.1  改变背景的积木······································50

4.3.2  动手做一做··············································50

4.4? 改变外观特效·········································51

4.5? 角色的显示和隐藏·································52

4.6? 改变造型························53

4.6.1  切换造型··························53

4.6.2  编辑造型··························54

4.7? 改变图层························54

4.7.1  图层的概念··············································54

4.7.2  改变图层的积木······································55

4.8? 综合实例：看我变变变·························56

4.8.1  任务描述··························56

4.8.2  构思和设计··············································56

4.8.3  编程实现··························57

第5章  让程序变得更“聪明”·························59

5.1? 流程图····························59

5.2? 条件执行积木········································60

5.3? 循环控制积木·········································61

5.4? 克隆积木························62

5.5? 其他控制积木········································63

5.6? 综合实例：大鱼吃小鱼·························64

5.6.1  任务描述··························64

5.6.2  构思和设计··············································64

5.6.3  编程实现··························64

第6章  用事件驱动程序执行·····························68

6.1? 事件类积木·············································68

6.2? 动手做一做·············································71

第7章  添加美妙的声音····································73

7.1? 声音类积木··············································73

7.2? 添加配音·························73

7.3? 播放声音·························74

第8章  积木中的“侦察兵”·····························75

8.1? 判断是否碰到或者是否按下····················75

8.1.1  积木介绍··························75

8.1.2  布尔运算（逻辑运算）···························76

8.1.3  动手做一做··············································77

8.2? 获取距离以及角色的属性·······················78

8.2.1  积木介绍··························78

8.2.2  动手做一做··············································79

8.3? 获取用户的输入······································81

第9章  运算类积木····················82

9.1? 运算类积木介绍·····································82

9.2? 动手做一做············································82

第10章  变量和列表·········································86

10.1? 变量和列表介绍····································86

10.2? 变量积木···············································87

10.3? 列表积木···············································87

10.4? 动手做一做···········································88

10.5? 综合实例：学生身高表的管理·····································89

10.5.1  任务描述························89

10.5.2  构思与设计············································89

10.5.3  编程实现···············································90

第11章  画笔积木·····················94

11.1? 画笔积木介绍········································94

11.2? 动手做一做···········································95

第12章  自制积木···················100

12.1? 自制积木介绍·······································100

12.2? 动手做一做··········································102

第二部分  计算思维及项目实例

第13章  计算思维···················110

13.1? 分解·······························110

13.2? 模式识别··············································111

13.3? 抽象化··························112

13.4? 算法开发··············································115

13.5? 计算思维的另一种表述························117

第14章 “打地鼠”游戏···································118

14.1? 任务描述···············································118

14.2? 问题分解··············································119

14.3? 角色设计及列表设置···························120

14.3.1  角色设计与制作··································120

14.3.2  列表和变量··········································121

14.4? 算法设计·············································123

14.5? 编程实现·············································128

第15章  四则运算测验····································131

15.1? 任务描述···············································131

15.2? 问题分解·············································132

15.3? 角色设计及变量设置···························132

15.3.1  角色设计与制作··································132

15.3.2  变量设置··············································135

15.4? 算法设计·············································135

15.5? 编程实现·············································139

第16章  画彩虹系列·······································144

16.1? 画彩虹和彩虹桥·································144

16.1.1  任务描述··············································144

16.1.2  问题分解··············································144

16.1.3  编程实现··············································145

16.2? 画彩虹圆和彩虹喇叭···························147

16.2.1  任务描述··············································147

16.2.2  问题分解··············································147

16.2.3  编程实现··············································148

第17章  冒泡排序法·······································151

17.1? 冒泡排序法简介····································151

17.2? 问题分解··············································153

17.3? 算法设计··············································154

17.4? 编程实现··············································155

附录A  常用的计算机操作和名词···················156

A.1? 鼠标操作（以右手操作为例）······································156

A.2? 名词解释··············································157

A.3? 文件管理和操作···································159

A.3.1  文件资源管理器简介·····························159

A.3.2  文件资源管理器的使用方法·········································161

附录B Scratch的所有积木····························163

B.1? 运动类···························164

B.2? 外观类··························166

B.3? 声音类··························169

B.4? 事件类··························170

B.5? 控制类···························171

B.6? 侦测类··························173

B.7? 运算类···························175

B.8? 变量类··························176

B.9? 自制积木·······················178

B.10? 画笔积木（扩展类）···························178

参考文献···································180

1. 注重基础知识和概念，讲解清晰而全面。

2. 数十个原创有趣实例，讲解循序渐进。

3. 39个动画视频，便于孩子自学。

4. 基于计算思维，提升孩子分析和解决复杂问题的能力。

5. 提供素材和源代码下载，资源丰富。