Healing Initial Model

1.B Develop an initial model of the healing process within and between multiple interacting systems and subsystems that restores the foot’s function.

Students’ first models on Healing Initial Model are more representative of what they see happening with the foot at a macroscopic level. As the handout suggests using close-up diagrams, and because students have practiced using them in previous 6th-grade units, you may notice some students adding these diagrams to their models to show what is happening under the skin (for example, that parts of the bone and muscle may no longer be connected underneath the broken skin). However, it’s not necessary for students to include cells or microscopic interactions at this time. Later in the unit, they investigate the structure and function of each part at the cellular level. Also, they are likely to suggest using a microscope to examine the injury at the microscopic level later in this lesson, during the Generate Ideas for Future Investigations activity. We want to be sure that students motivate the need to explore this phenomenon at different scales.

If students need support in choosing what to put in their models, refer them back to the Healing Timeline we developed as a class. Ask what they think might be happening with each part of the foot between when the injury happened until the student could walk again. Ask what was different in the parts of the foot right after the injury and after it was healed.

Students might include parts of the foot without representing how the parts interact or work together. If you notice this, remind them that we can also think about what’s going on inside the foot and underneath the skin because x-rays allow us to see some internal structures. Prompt them to include how the parts were interacting during the events in the Healing Timeline, and what we might see if we could look inside the foot at these interactions.

Healing Initial Model handouts can be collected (at the end of the class) and used as a formative pre-assessment. They can help identify what science ideas students are bringing into this unit and where students are in their development of the practice of modeling.