Based on your query, both Beautiful.ai and Canva could be excellent tools for creating presentations. However, Canva seems to offer a more comprehensive solution for educators.

Canva provides a user-friendly platform with a drag-and-drop feature, making it easy for users of all skill levels to create visually engaging content. It also integrates with core classroom tools such as Google Classroom and Microsoft Teams, which could be beneficial for sharing your presentations with students.

One of the standout features of Canva is its vast library of templates. These can be a great starting point for your presentations, saving you time and ensuring a professional look. Additionally, Canva offers free access for educators and students, which could be a significant advantage if budget is a concern.

Canva also has several AI features that could be useful. For instance, the "Magic Write" AI text generator could help you generate written content for your presentations, while the "Magic Design" tool uses AI to generate relevant design templates based on a photo upload or a text query.

In conclusion, Canva could be a great tool for creating presentations due to its user-friendly interface, integration with classroom tools, vast template library, and AI features.