Based on your search query, Whimsical seems to be an excellent fit. It's a feature-rich digital workspace designed to facilitate visual thinking and collaboration, making it ideal for middle school students.

Here's how Whimsical can address your needs:

1. Mind Mapping: Whimsical provides a robust mind mapping tool that can help students visualize complex ideas and concepts. This can aid in comprehension and retention, especially for middle school students who are still developing their abstract thinking skills.

2. Collaboration: The platform supports real-time collaboration, allowing students to work together on a single document. This feature can be particularly useful for group projects and interactive learning.

3. Customizable Templates: Whimsical offers a variety of customizable templates to suit different needs. This adaptability makes it a versatile tool that can be used across various subjects.

4. AI-powered Suggestions: The AI-powered suggestions for mind maps can help students generate new ideas instantly, aiding in overcoming mental blocks during brainstorming sessions.

5. Text-to-Flowchart Feature: This tool can translate students' ideas into flowcharts in seconds, which can be particularly useful in subjects that require process-based thinking.

6. Free for Educational Use: Whimsical offers an education plan that allows teachers and students to use the platform free of charge, making it a cost-effective tool for educational institutions.

In summary, Whimsical is a comprehensive tool that can enhance the learning experience for middle school students by promoting visual thinking, collaboration, and creativity.