What are four tools you can use to make quantitative observations

Quantitative is how many or a measurement. You can take a measurement with:
a ruler
thermometer
weight scale
stop watch
Hope this helps. 

A ruler, a bathroom scale, a clock, your heartbeat, a car speedometer, a car odometer, a photographer's light meter, a voltmeter, and a kitchen measuring cup can all deliver quantitative measurements.

Aform of energy that is reflected or emitted from objects in the form of electrical and magnetic waves that can travel through space. there are many forms of  electromagnetic  energy including gamma rays, x rays, ultraviolet radiation, visible light, infrared radiation, microwaves and radio waves.

Amethod of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.