Lesson Plan Template: General Lesson Plan
Learning Objectives: What should students know and be able to do as a result of this lesson?
Students will understand how to use a strategy based on place value and related to a written method (procedural), to add and subtract decimals (through hundredths place), in money form.
Prior Knowledge: What prior knowledge should students have for this lesson?
Students should be able to add and subtract whole four-digit numbers fluently. (MAFS.3.NBT.1.2)
Students should be able to read decimals to the hundredths place. (MAFS.5.NBT.1.3)
Guiding Questions: What are the guiding questions for this lesson?
Opening of lesson:
How is adding and subtracting decimals the same as with whole numbers?
How do you think adding and subtracting decimals is different than adding and subtracting whole numbers?
Why is place value important when adding decimals?
Looking back at our example of movie tickets, what do the decimal places represent in money amounts?
What value does each place value have?
What does it mean when your decimal has a zero in a place value?
What happens when you have more than 9 tens?
Teaching Phase: How will the teacher present the concept or skill to students?
Teacher passes out store flyers to use as reference for lesson.
The teacher will involve the class in a discussion about their experiences of buying items at a store.
The students will provide examples of what they'd like to buy out of the flyer and the cost of the item (any item and reasonable price should be accepted).
The teacher will use one example and ask what the digits in the price means?
Example: $25.34. Possible question, "What is the value of the 3 in the price?" (3 tenths, 3 dimes, 30 cents) Your'e looking for students to explain that the 2 is in the tens place or 2 tens and represents $20.00. The 5 is in the ones place, it's 5 ones, and represents $5.00, the 3 is in the tenths place, it's 3 tenths and represents 30 cents or 3 dimes, the 4 is in the hundredths place, it's 4 hundredths, and represents 4 cents or 4 pennies.
The teacher hands out bags of base tens blocks to students. The teacher asks students what they think each base-ten block will represent in a decimal. Guide students to relate that small blocks will represent 1 cent or hundredths, longs will represent 10 cents or tenths (ten of the hundredths), and flats will represent $1.00 or ones (ten of the tenths).
The teacher picks an item (before the lesson) whose price is less than $3.00, but also has a large tenths and hundredths value. An example would be $2.98. (This choice ensures that there are enough blocks and that regrouping can be modeled later). Students are asked to represent the price with base-ten blocks. The teacher should walk around and look for various representations to use as examples. Examples chosen should attempt to represent a variety of methods and possible misconceptions. The teacher asks her example students to help her record a model of their base-ten representations on chart paper and guides discussion about the place values. Students should not take apart this model.
The teacher picks another previously chosen price from the flyer whose price is less than $3.00 which will ensure a modeling of regrouping in the next step. The class models with base-ten blocks. The teacher then records the modeling on chart paper as before.
Now the teacher asks students how they would represent the addition of these prices with the base-ten blocks. Teacher records students solutions on chart paper and guides discussion about what happens with decimal place values when regrouping is needed. Students offer solutions and demonstrate their thinking on chart paper or white board. The teacher guides students to see how to regroup with base-ten blocks. Example attached.
Regrouping modeling example
The teachers asks if students may see a more efficient way to add decimals.
The class views Study Jams video and then do 2 practice problems at the end of the video, as a class. (Do not do Test Yourself section until later).
Guided Practice: What activities or exercises will the students complete with teacher guidance?
Refer again to store flyers and pass out place value guide. The teachers guides students to label the place values on the guide.
place value guide
The teacher then asks students for suggestions on what items they'd like to buy in the sales flyer?
When 2 items are chosen the teacher guides and models how to fill the prices into the place value guide.
- question what each place value represents in each price. Example: Beach chair $12.95. What is the value of the 1 in the price? (1 ten or $10.00) How many tenths are in the price? (9 tenths) How many hundredths are in the amount? (5 hundredths or 95 hundredths)
Teacher will ask students for ideas on how they would add two of these items to get a total, reminding of what they learned from their modeling and the Study Jams video.
Teacher will ask various students for choices of 2 items they want to buy from the flyer. Teacher guides class through algorithm under document camera, using the four column chart, while students do on their own charts. Teachers checks for understanding and provide feedback.
Teacher will then ask students for situations of when we may subtract money amounts, using the store flyers for examples.
Teacher asks students for an example and guides class through algorithm under document camera while students do on charts. Teacher checks for understanding and provide feedback.
The teacher guides students to more examples which include those where the total is known, but item price is not.
- You're buying a hat for $4.45. You pick up an umbrella to buy and your total is now $12.85. What is the price of the umbrella? (answer: $8.40)
- You're purchasing some paper ($2.50), pencils ($1.75), and markers ($4.65) for school. When you get to the counter you decide you want some gum as well. The cashier tells you your total is $10.46. How much was the gum? (answer: $1.55)
Independent Practice: What activities or exercises will students complete to reinforce the concepts and skills developed in the lesson?
Pass out Independent Practice worksheet.
Independent Practice Worksheet
The students will use store flyers and work with a partner on 2 shopping trips examples. Each shopping trip asks students to chose 3 items from the flyer and to calculate the total for these items. They are asked to subtract a coupon amount from their total. Finally, they'll need to calculate a missing price from their total.
Closure: How will the teacher assist students in organizing the knowledge gained in the lesson?
Students will share success and struggles they encountered during independent practice.
Teacher will guide discussion and ask students for suggestions to help classmates and clear up misconceptions.
- make sure to guide discussion regarding place value. An example would be if your price was $4.32 what is the value of the 3?
- make sure to guide the discussion about regrouping. An example would be if you added two prices $4.37 and $5.77, what did you do with the sum of the hundredths place?
The teacher will introduce "Shopping Trip for the Beach" assessment and explain expectations. See Summative Assessment phase.
Students will calculate the cost of items they are purchasing for a trip to the beach. Students are expected to use regrouping/written method on assessment unless accommodations are pre-arranged during lesson.
Use this Formative Assessment to assess prior knowledge and to assess knowledge of the concepts in this lesson.
Questions 1 - 3 assess prior knowledge and question 4 assesses knowledge of the current lesson.
This assessment would be given the day before the lesson so that a teacher can review possible need for reteaching or extensions.
Feedback to Students
Use the Guided Questions during the lesson to continue to assess student thinking and provide feedback.
Students will be given feedback during the teaching phase and guided practice when they show their work under the document camera and on individual white boards
Students will have an opportunity to improve their performance during guided practice and independent practice.