Objects could include vessels, kitchen utensils, tools of various types, disassembled parts of larger objects. Be creative and include a few things the students may not readily recognize or be familiar with.
Duplicates are fine.
They are studying the objects found in these different households in order to compare similarities and differences from family to family. Each group of 5 students is given a set of artifacts. Describe, measure and draw each object Classify the objects. Each object may be in a different category or they may choose to group certain items together. Explain to the class their classification system, how the artifacts were classified and why.