Converting Between Fractions and Decimals Using Visual Models
Objective
Students will analyze relationships between fractions and decimals by creating visual representations and working collaboratively to solve conversion problems.
Materials
- Grid paper
- Colored pencils or markers
- Rulers
- Calculators
- Chart paper
Hook
Partners receive different cards showing either a fraction or decimal (like 0.75 and 3/4) and must find their match by walking around the room, then discuss how they knew the values were equivalent.
Main Activity
Working in pairs, students create visual models on grid paper to represent fraction and decimal equivalents, using 10×10 grids to shade areas representing values like 1/2, 0.25, 3/5, and 0.8. Each pair chooses four fraction-decimal pairs and creates large poster presentations showing their visual models alongside written explanations of the conversion process. Teams rotate to view other posters and verify the accuracy of conversions using calculators. Partners then collaborate to solve real-world problems involving fraction and decimal conversions, such as calculating discounts, measuring ingredients, or comparing sports statistics.
Discussion Questions
- How does shading a 10×10 grid help you understand the relationship between fractions and decimals?
- When might it be more useful to express an answer as a fraction versus a decimal in real life?
- What patterns do you notice when converting fractions with denominators of 10, 100, or 1000?
- How can you check if your fraction to decimal conversion is correct without using a calculator?
- Why do some fractions create repeating decimals while others create terminating decimals?
Exit Ticket
Convert 3/8 to a decimal and draw a visual model to show your work, then explain your conversion strategy in one sentence.
Differentiation
Support: Provide pre-drawn grids with partial shading and focus on simple fractions with denominators of 2, 4, 5, and 10 that convert to terminating decimals.
Extension: Challenge students to explore repeating decimals by converting fractions like 1/3 and 2/9, then investigate patterns in the repeating digits and create rules for predicting which fractions will produce repeating versus terminating decimals.
