Lesson: Unit Conversions: Liters & Milliliters
Vocabulary: Customary, Metric, liters, milliliters, volume, multiplication, division, formula
Do Now (5-7min): The teacher holds up an empty 1-liter container. Teacher says “For the past couple of days, we have been talking about units of measure in the Customary system that measure volume. Today we are going to talk about a Metric unit of measurement that measures volume. This is a one-liter container and I want you all to take a minute to guess how many milliliters are in this one-liter container. I will give you a hint.” Teacher writes the numbers 10, 100, 1000, 10000 on the board and says, “I told you several days ago that the Metric system is based on the number 10, just like in place value. So your hint is that the number of milliliters in a liter is a base 10 number.”
Opening (3-5 min): Teacher says, “Ok, how many students guessed that there are 10 milliliters in one liter? How many guessed that there are 100? How many guessed that there are 1,000? How many guessed that there are 10,000? Great, you all had some great guesses; the correct answer is that there are 1,000 milliliters in one liter. So, today, we are going to talk about two units of measurement: liters and milliliters. Who can remind the class what system of measurement these units belong to?” [Metric]
Teacher should state objective at end of the opening, “Very good! Today we are going to talk about the relationship between liters and milliliters. By the end of this lesson, you will all be able to convert milliliters to liters and liters to milliliters.”
Direct Instruction (7-10min): Teacher holds up the empty 1-liter container and says, “This is the same container that you all used during your Do Now, and this container is exactly one-liter large. Can someone tell me how many milliliters are in this container?” [1,000] “Good, so that means that there are 1,000 milliliters in every liter.” Teacher writes 1 liter = 1,000 milliliters on the white board. Teacher holds up an empty two-liter bottle and says, “So if I had a two-liter container of soda, how many milliliters of soda would I have?” [2,000 milliliters]
Teacher writes 2 liters = 2,000 milliliters on the board and says, “That’s great, so we know that 2 liters is equal to 2,000 milliliters. Ok, who can tell me what sort of math they used to decide that 2 liters is equal to 2,000 milliliters?” [I added, I multiplied, I divided, I counted on my fingers, etc.] Teacher writes the word milliliter on the board and says, “Ok, I hear a lot of great answers, but I want to make one thing very clear, when you are talking about milliliters and liters, which unit is smaller?” [Milliliter] Teacher writes smaller next to milliliter and says, “Which unit is bigger?” [Liter] Teacher writes liter and bigger on the board and says, “If I want to go from milliliters to liters, which math operation would I use since milliliters are smaller than liters?” [Division] Teacher writes the division sign under the word milliliters and says, “Great! If I want to go from liters to milliliters, since a liter is bigger than a milliliter, which math operation would I use?” [Multiplication] Teacher writes the multiplication sign under the word liter.
Teacher says, “Fantastic! When we are converting back and forth between milliliters and liters, we use the multiplication and division operations. To make this easier to understand, I am going to show two formulas.” Teacher writes milliliter ÷ 1,000 = liter and liter x 100 = milliliter on the board and says, “Can someone guess why I put a 1,000 in both formulas? [Because there are 1,000 milliliters in a liter] This is a very important point to remember when we are converting Metric units of measurement. Remember, the Metric System is based on multiples of 10, just like place value. Therefore, multiplying and dividing with the Metric system, even with big numbers, shouldn’t be intimidating! Watch, and let’s practice.”
Guided Practice (15-20 min): Teacher passes out the GP Unit Conversion worksheet and writes the following on the board:
1. 9 liters = ______ milliliters [9,000]
2. 5 liters = ______ milliliters [5,000]
3. 4,000 milliliters = ______ liters 
4. 6 liters = ______ milliliters [6,000]
5. 10 liters = ______ milliliters [10,000]
6. 4,000 milliliters = ______ liters 
7. 3 liters = ______ milliliters [3,000]
8. 7,000 milliliters= ______ liters 
9. 2,000 milliliters = ______ liters 
10. 4 liters= ________ milliliters [4,000]
The teacher says, “Alright, the best way to learn how to convert units of measurement is to practice. I have written ten different problems on the board. We are going to solve these together. I will do the first one and show you how to fill in the steps on your GP Conversion Worksheet. Then we will do the rest together, but please remember to complete all problems on your GP Worksheet.” Teacher goes through each problem, demonstrating how to choose which formula to use and modeling how to write the formula for every problem. Students should be called on through the guided practice for answers.
Independent Practice (10 min): Teacher gives each student their own copy of the Independent Practice (IND) worksheet. Teacher circulates the room to answer individual student’s questions.
Closing (2-3 min): Teacher calls the attention of the students back toward the front of the class to quickly review the answers to the Independent Practice worksheet.
|IND Practice Milliliters and Liters Classwork||
|GP Unit Conversion Template Classwork||