Summary

Attached you will find everything you need to help your students gain a better understanding of density, buoyancy and Archimedes' principle.Uploaded files will provide you with two complete labs kits.

Lab #1:
Investigating Volume - understanding cm cubed and mL

Lab #2:
Investigating Density and Buoyancy

Instructions

For Lab #1: Investigating Volume - understanding cm cubed and mL

Print two cmcube.stl cubes per group.
Print the first cube using standard settings and using 5% infill.
Print the second cube using standard settings and using 100% infill. This will ensure that one cube will float and the second will sink. Do not let students know that they have two different cubes, they will discover this on their own.
Print and use the "Investigating Volume - understanding cm cubed and mL.pdf" as a guide to your investigation.
I have successfully completed this lab with grade 8 students who completed the lab with a deep understanding of how mL and cm^3 are related.
This lab is also an excellent introduction to density. Students will be able to describe why one cube will float and the second will sink based on what they know of volume and mass. Be prepared with massing devices as students will want to compare the mass of both of their cubes. Students have also created their own procedure for creating a neutral buoyancy cube, this is a great extension project.

For Lab #2: Investigating Density and Buoyancy

Print a cylindricalboat.stl and cylindricalboatmold.stl per group.
Print the cylindricalboat with standard settings at 100% infill. This will ensure that your boat has a density greater than 1 g/mL. No raft or supports are needed.
Print the cylindricalboatmold with standard settings and 10% infill. Once printed, inspect the joins of the mold, you may need to use glue as a sealant to ensure that it won't leak. Alternatively you can print with 100% infill.
Print the "Investigating Density and Buoyancy.pdf" as a guide to your investigation.
I have not had a chance to use this experiment with students yet, but have run through the lab myself. You may need to add food colouring to your water when using the mold to be able to see the water level with greater clarity. I am excited to try this lab with students in the coming year...

Density and Buoyancy Investigations