A kindergarten teacher is responsible for planning the curriculum for each day and for the collective school year. Teachers must allow the children to observe an activity while also giving them the opportunity to ask questions and look for the answers. Instructions need to be very precise yet easy to understand.
The CS220 is a thermocouple that measures the temperature of a surface by direct contact. SI-111 Infrared Radiometer with Standard Field of View. The SI-111, manufactured by Apogee, is a precision infrared radiometer that determines the surface temperature of an object without physical contact.
If you are not measuring it to a tenth of a degree, then it doesn't matter all that much. But check the accuracy of the devices you use. What you need to look at is the range that the thermometer measures, and compare this to the likely temperatures of the water you need to check. If you are measuring the temperature of water in a room after standing a while, the temp. is likely to be under 25 (Celsius). If the water is cooling down (or heating up) then you might need a range up towards 100 (Celsius), and if it's towards freezing, you need something that gets to 0 Celsius.