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    Explore what CodeHS has to offer for districts, schools, and teachers.

    • Coding LMS
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    • Districts
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  • Products Explore what CodeHS has to offer for districts, schools, and teachers
    • Coding LMS
    • Online IDE
    • CodeHS Pro
    • Computer Science Curriculum
    • Certifications
    • Professional Development
    • Use Cases
      • Districts
      • Schools
      • Teachers
  • Platform
    • Assignments
      Create & configure your course assignments
    • Classroom
      Manage & organize your class with customizable settings
    • Grading
      Streamline your grading workflow.
    • Data
      Track & analyze student assessments & progress data
    • Write Code
      Write, run, & debug code all in a web-based IDE
    • Integrations
      Connect CodeHS to your district’s educational platform
  • Platform
    • Assignments
      Create & configure your course assignments
    • Classroom
      Manage & organize your class with customizable settings
    • Grading
      Streamline your grading workflow.
    • Data
      Track & analyze student assessments & progress data
    • Write Code
      Write, run, & debug code all in a web-based IDE
    • Integrations
      Connect CodeHS to your district’s educational platform
  • Curriculum

    Computer Science Curriculum

    Customizable K-12 Computer Science Curriculum

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  • Curriculum Customizable K-12 Computer Science Curriculum
    • Course Catalog
      • AP Courses
      • Interdisciplinary
      • Hour of Code
      • Spanish Courses
    • K-12 Pathways
      • Elementary
      • Middle School
      • High School
    • States
    • Standards
    • Practice
    • Tutorials
    • Digital Textbooks
  • Professional DevelopmentPD

    Professional Development

    Online & In-Person Training for Teachers

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    • Online PD Courses
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  • Professional Development Online & In-Person Training for Teachers
    • Professional Development
    • Online PD Courses
    • In-Person & Virtual Workshops
    • Free PD Events
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  • Online IDE

    Online IDE

    Write, Run, & Debug Code in an Online IDE

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  • Online IDE Write, Run, & Debug Code in an Online IDE
    • Online IDE
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New Sandbox Program

Click on one of our programs below to get started coding in the sandbox!

Java

JavaScript

Python 3

HTML

Karel

Turtle

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Exercise Complete Allele Collection

5 points

This code has diverged from the student’s work.
Hour of Code: Punnett Squares
Finish My Hour of Code