---
title: thumbnail
framework: classkit
role: symbol
role_heading: Instance Property
path: classkit/clscontext/thumbnail
---

# thumbnail

An optional thumbnail image associated with the context.

## Declaration

```swift
var thumbnail: CGImage? { get set }
```

## Discussion

Discussion Schoolwork displays the thumbnail along with your content to help teachers and students more easily recognize a given context. For example, you could use a variation of your app icon for your main app context, an open book for a reading exercise, or a calculator to represent a math quiz. Create thumbnails that match the style of your app. The image you provide should have at least 80 pixels on a side, and at most 330 pixels. ClassKit won’t use an image that’s too small, and automatically scales down an image that’s too large. For the best experience across all devices, use an image that’s close to or at the maximum dimensions.

## See Also

### Identifying the context

- [identifier](classkit/clscontext/identifier.md)
- [title](classkit/clscontext/title.md)
- [summary](classkit/clscontext/summary.md)