Merge pull request #572 from code-dot-org/staging

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Merge pull request #575 from code-dot-org/test

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Merge pull request #577 from code-dot-org/staging

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Merge branch 'staging' into test
Merge branch 'staging' into test
Merge pull request #579 from code-dot-org/test

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hotfix educator notes link
Merge branch 'test' into staging