Based on your query, I would recommend using DreamStudio. This web-based application uses artificial intelligence to generate images from text prompts, which could be used to create avatars from descriptions.

Here's how it could work for you:

1. AI Image Generation: You can input a text description of the desired avatar, and DreamStudio will generate an image based on this prompt. This could be a fun and engaging way for students to create their own unique avatars.

2. Adjustable Image Elements: The application allows you to adjust the style, number, and other elements of the image. This means students can customize their avatars to their liking, making each one unique.

3. Downloadable Images: Once the avatar is generated, it can be downloaded for use. This could be useful for incorporating the avatars into online learning platforms, student profiles, or class projects.

Remember, DreamStudio operates on a credit system, with each credit valued at approximately $0.01. New users receive 25 free credits, so you can try it out and see if it meets your needs before purchasing more credits.