The core principles of effective instructional design include:

1. Learner-Centered Approach: Focus on the needs, backgrounds, and learning styles of the learners.
2. Clear Learning Objectives: Define specific, measurable goals for what learners should achieve.
3. Engagement: Incorporate interactive elements and real-world applications to maintain interest.
4. Scaffolding: Build on prior knowledge and gradually increase complexity.
5. Assessment and Feedback: Use formative and summative assessments to evaluate progress and provide constructive feedback.
6. Flexibility: Adapt instructional strategies based on ongoing evaluation and learner feedback.
7. Accessibility: Ensure materials are usable for all learners, including those with disabilities.

These principles help create effective, inclusive, and engaging learning experiences.