Fraction Clinic Teacher Guide Fraction Clinic
Teacher Facilitation Guide
Subject
Mathematics: Fractions
Grade Level
5th Grade
Duration
45-50 Minutes
Learning Objective
Students will identify and correct errors in fraction subtraction with unlike denominators by finding equivalent fractions and simplifying results.
Lesson Timeline
1
The Emergency Room Hook (5 min)
Show the "Broken Problem" on Slide 2: \(1/2 - 1/4 = 0/2\).
Ask: "Is this patient's math healthy? Why or why not?"Key Misconception: Subtracting across (numerators and denominators).
2
Diagnostic Training Video (15 min)
Watch the "Subtraction of Unlike Fractions" video. Focus on the Yellow Sidebar process.
Pause at 0:18: Ask what the first step must be.Pause at 0:50: Discuss why \(2/10\) isn't the final "healthy" answer (needs simplifying).
3
The Error Doctor Activity (20 min)
Students receive "Patient Files" (Worksheet). They must:
Check if the math is "Healthy" or "Needs Treatment."
Diagnose the specific error.
Apply the "Treatment" (solve it correctly).
4
Medical Boards Reflection (5 min)
"Doctors, what was the most common 'virus' you found today? How can we prevent it in our own work?"
Diagnostic Key for Teachers
Patient Case Status The Diagnosis (What's Wrong?) \(3/4 - 1/8 = 5/8\) HEALTHY No error. Correctly converted to \(6/8 - 1/8\). \(4/5 - 1/2 = 3/3\) NEEDS TREATMENT Subtracting across. Did not find a common denominator. \(2/3 - 1/6 = 1/6\) NEEDS TREATMENT Numerator neglect. Changed the denominator to 6 but didn't multiply the numerator. \(5/6 - 1/3 = 1/2\) HEALTHY Correctly solved as \(5/6 - 2/6 = 3/6\), then simplified to \(1/2\). \(7/10 - 1/5 = 5/10\) NEEDS TREATMENT Incomplete Recovery. The subtraction is correct, but the answer isn't simplified (lowest terms).
Differentiated "Treatment" Strategies
Support
Provide a "Prescription Pad" with blank templates for finding equivalent fractions (multiplying boxes).
Challenge
Ask students to create their own "Sick Problem" and trade with a partner for surgery.
Fraction Clinic Slides Medical Training Session
FRACTION
CLINIC
Diagnosing & Treating Unlike Fractions
ER Case #001
Patient Work:
\[ \frac{1}{2} - \frac{1}{4} = \frac{0}{2} \]
Diagnose
Is this math healthy? Why not?
Brainstorm
What did the student do wrong?
Expert Consultation
Observation Phase
Embedded media
The Yellow Sidebar
Watch for the sidebar! This is where we perform equivalent fraction surgery.
Discussion Prompts
Why can't we subtract unlike fractions yet?
What determines our common denominator?
Diagnostic Steps
Step 01
Identify
Check the denominators. Are they the same? If not, we have Unlike Fractions.
Step 02
Convert
Find an Equivalent Fraction to create common denominators.
Step 03
Simplify
Check your final answer. Is it in its simplest form? Divide by common factors!
The Error Doctor
I am handing out 5 Patient Files. Some patients have healthy math, but most are suffering from common fraction viruses. Your mission: find the errors and perform surgery!
1. Find Error
2. Explain Why
3. Treat It
Error Doctor Worksheet Fraction Clinic
Patient File: The Error Doctor
Doctor Name:
Date:
Medical Instructions:
Carefully examine each patient's subtraction work. Identify if the math is Healthy or Needs Treatment. If it needs treatment, diagnose the error and show the correct "surgery" in the treatment box.
CASE #01
Healthy
Needs Treatment
Patient's Math
\( \frac{3}{4} - \frac{1}{8} = \frac{5}{8} \)
Diagnosis & Treatment
CASE #02
Healthy
Needs Treatment
Patient's Math
\( \frac{4}{5} - \frac{1}{2} = \frac{3}{3} = 1 \)
Diagnosis & Treatment
CASE #03
Healthy
Needs Treatment
Patient's Math
\( \frac{2}{3} - \frac{1}{6} = \frac{1}{6} \)
Diagnosis & Treatment
CASE #04
Healthy
Needs Treatment
Patient's Math
\( \frac{5}{6} - \frac{1}{3} = \frac{1}{2} \)
Diagnosis & Treatment
CASE #05
Healthy
Needs Treatment
Patient's Math
\( \frac{7}{10} - \frac{1}{5} = \frac{5}{10} \)
Diagnosis & Treatment
Medical Board Reflection
Of the errors you found today, which one do you think is the easiest "virus" to catch? Why?
Error Doctor Answer Key Fraction Clinic
Answer Key: The Error Doctor
CASE #01
Healthy
Patient's Math
\( \frac{3}{4} - \frac{1}{8} = \frac{5}{8} \)
Notes
This math is healthy! The student correctly converted \(3/4\) to \(6/8\) and subtracted correctly.
CASE #02
Needs Treatment
Patient's Math
\( \frac{4}{5} - \frac{1}{2} = \frac{3}{3} = 1 \)
Treatment
Diagnosis: Subtracting numerators and denominators across.
\( \frac{8}{10} - \frac{5}{10} = \frac{3}{10} \)
CASE #03
Needs Treatment
Patient's Math
\( \frac{2}{3} - \frac{1}{6} = \frac{1}{6} \)
Treatment
Diagnosis: Changed denominator to 6 but forgot to change the numerator of 2/3.
\( \frac{4}{6} - \frac{1}{6} = \frac{3}{6} = \frac{1}{2} \)
CASE #04
Healthy
Patient's Math
\( \frac{5}{6} - \frac{1}{3} = \frac{1}{2} \)
Notes
Healthy! Subtraction was correct (\(5/6 - 2/6 = 3/6\)) and then simplified correctly (\(1/2\)).
CASE #05
Needs Treatment
Patient's Math
\( \frac{7}{10} - \frac{1}{5} = \frac{5}{10} \)
Treatment
Diagnosis: Subtraction is correct, but result is not simplified (not in lowest terms).
\( \frac{7}{10} - \frac{2}{10} = \frac{5}{10} = \frac{1}{2} \)
