well, you can go to other sites
with some Styrofoam balls
Dont be an idiot 5 year olds can't use 3D Editing software.
you build it
How to make a model of an energy class science project
Grade 6 can make science investigatory project Like: Horsetail can make us beautiful. Electromagnet. Guava can make into soap. Ashitaba leaves.
You don't make it its hard
Making a volcano for a 6th grade project is very simple. Make the volcano out of paper mache and use baking soda and vinegar for the explosion.
how to make a heart model for science fair project
Since grade 7 is usually Life Science, make a cell model. You could also do a Global Warming project, which would show environmental impact, and whether it is actually real or just a hoax. If whoever it is in seventh grade is working on this, you could do densities or masses. Or the planets (interia, ellipses, eclipses, ect.)
how make this house
You can make a model of a human heart by making it with candy, clay, and Tupperware. If this is for a school project I suggest something creative like candy which can shoot up your grade. Tupperware may be a good idea but it's harder.
I'm also a fifth grade student, and my project idea might be about photosynthesis [ how plants make food from sunlight].