Based on your query, I would recommend Beautiful.ai as it seems to be the most suitable tool for your needs.
Beautiful.ai is designed to make creating presentations fast and simple. It uses machine learning and natural language processing to pick out important parts of your slides and make them look good without you having to be a design expert. This is particularly useful for teachers who want to make lessons visually appealing but may not have the time or skills for design.
The Design AI feature automatically figures out the best design for your slides, saving you time and effort. The Drag-and-Drop Editor and Templates make it quick to build slides, allowing you to focus more on the content and less on the look.
Additionally, the Team Collaboration feature allows you to work with other teachers or students in real-time, which can be helpful for group projects or when you need to make a school-wide presentation.
However, please note that Beautiful.ai does not have a totally free version and some users have mentioned that you have to pay yearly to get a good deal. If this is a concern, you might want to consider the other options.