[null,null,["最后更新时间 (UTC)：2025-08-29。"],[],[],null,["# Attachments\n\n**Attachments** are the pieces of content that users view and interact with.\nThis guide provides a brief overview of attachments in Google Classroom and\ndefines some important attachment-related terminology.\n\nAt a very high level, *an add-on's role is to create and manage attachments* .\nAdd-ons provide an opportunity for students to access your content directly\nwithin Google Classroom. Unlike assignments created using the [CourseWork\nAPI](/workspace/classroom/reference/rest/v1/courses.courseWork), add-on attachments support your customized and interactive experiences\nwithout requiring the user to leave Google Classroom.\n\nTeachers add attachments to **assignments**. An assignment can have up to ten\nattachments, though only eight of any single type. Examples of attachments\ninclude YouTube videos, Google Docs, or external links. You can also attach\nfiles from Google Drive or uploaded from your computer.\n\n**Figure 1.** Attachments appear as cards when creating, viewing, or completing\nan assignment.\n\nAttachment types\n----------------\n\nThere are two types of add-on attachments: **activity** and **content**.\nActivity-type attachments are any that require a student submission or turn-in\naction, such as a quiz or written response. Content-type attachments are\nview-only materials that don't require a student submission, such as videos or\nnews articles.\n| **Note:** Consider automatically saving progress as students work through activities. Doing so may prevent user frustration; a student may be unable to complete an activity in a single session or they might navigate away from the activity before completing their work.\n\nAttachment-related API interactions differ slightly depending on the attachment\ntype. For details regarding interactions with attachments through the add-ons\nAPI, visit the [Interacting with attachments](/workspace/classroom/add-ons/developer-guides/attachment-interactions) guide page.\n\nAutomatically graded attachments\n--------------------------------\n\nYou can **pass grades back to Google Classroom** for activity-type\nattachments. Doing so populates the grade field for a particular assignment with\na draft grade. The grade can be any decimal number zero or greater. See our\n[Interacting with attachments](/workspace/classroom/add-ons/developer-guides/attachment-interactions) guide page for implementation details.\n\nNote that *this is a heavily requested feature by teachers*; our user experience\nresearch has shown that many teachers assume that add-on activity grades are\nautomatically be returned to Google Classroom.\n\nCreate attachments from a third-party site\n------------------------------------------\n\nYou can create add-on attachments programmatically from outside of\nGoogle Classroom. The interactions are similar to [creating assignments using\nthe CourseWork API endpoints](/workspace/classroom/guides/manage-coursework#create_assignments). See the dedicated [Create attachments outside of\nGoogle Classroom](/workspace/classroom/add-ons/developer-guides/third-party-first-journey) guide for implementation details."]]
