I need to preform an ohm's law eksperiment with 3 1.5V bateries, an reostat, a unknown resitor, an ammeter and a voltmeter. How do I put it together and show that it works.. HELP please?

You have to show that the current flowing through the resistor is directly proportional to the voltage applied across the resistor, provided all other physical constants are constant (ie temperature, etc).

Such a resistor is then an Ohmic resistor.

So, you need to connect the ammeter so that it's in series with the batteries and resistor, the voltmeter across the resistor, and the rheostat will be connected in series with the ammeter, batteries and resistor.

Thank you :)