Start with 30 turns on your small copper wire coil. This you can vary later. The mini-phone jack plugs into the headphone socket on a small transistor radio. Nothing needs to be tape recorded, you are merely using the meter for taking measurements. These measurements will need to be recorded on a data chart of your own design.
All equipment is crude, cheap, and available at most schools.
As a research team, you will need to determine what variables might be manipulated to improve the quality of your tin can speaker. Once your team has determined which variables you will be changing, you need to design a data chart to record the VU's for each variable change you try. Be sure to include your data chart and any graphs you might have made. Demonstrate your tin can speaker to your instructor.