# Why does code.org still use var?

**URL:** <https://forum.code.org/t/why-does-code-org-still-use-var/40747>\
**Category:** All Courses: Pedagogy and Best Practices\
**Created:** [May 12, 2025, 7:42pm UTC](https://forum.code.org/t/why-does-code-org-still-use-var/40747 "2025-05-12T19:42:05Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![189249](https://avatars.discourse-cdn.com/v4/letter/1/9f8e36/32.png) [@189249](https://forum.code.org/u/189249)\
**Post date:** [May 12, 2025, 7:42pm UTC](https://forum.code.org/t/why-does-code-org-still-use-var/40747/1 "2025-05-12T19:42:05Z")

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It seems weird to teach kids to use an outdated way of declaring variables. I know that [code.org](http://code.org) isn’t on ES6 yet, but I feel like that should be a priority. (same issue with default parameters for functions)

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**Author:** ![varrience](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.code.org/varrience/32/8042_2.png) [@varrience](https://forum.code.org/u/varrience)\
**Post date:** [May 13, 2025, 5:12am UTC](https://forum.code.org/t/why-does-code-org-still-use-var/40747/2 "2025-05-13T05:12:56Z")

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if you are aware of how CDO works, you would know that it uses an interpreter to run the code. Meaning that it’s running it’s own custom sand-boxed version of ES5 to migrate to ES6 would be a huge undertaking! Not to mention many of the lessons would have to be changed or redone entirely because of this. Additionally a bunch of personal projects on the site would break due to the changes built on ES5 architecture and possibly some more new ES6 exploits. And as you know CDO is a voluntary organization if you think you are capable of this change feel free to add it yourself on the github which should be under the name of code-dot-org, either that or feel free to ask the support team yourself (although i don’t think they would know)