In this lesson students will learn about the basic concept of interest. Students will discover how certain savings accounts may earn interest and how borrowing money can require paying interest, helping them understand that interest can either help money grow or make borrowing more expensive.

Lesson 8: How Does Interest Work?

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`; q.choices.forEach(function(choice,choiceIndex){ html += ` `; }); html += `
`; }); container.innerHTML = html; } /* ===================================== GRADE QUIZ ===================================== */ window.gradeLesson8Quiz = function(){ var score = 0; var unanswered = 0; questions.forEach(function(q,index){ var selected = document.querySelector( 'input[name="lesson8q' + index + '"]:checked' ); var feedback = document.getElementById( "lesson8feedback" + index ); if(!selected){ unanswered++; feedback.style.display = "block"; feedback.style.background = "#fff7ed"; feedback.style.color = "#9a3412"; feedback.innerHTML = " Please answer this question."; return; } var selectedAnswer = parseInt(selected.value); if(selectedAnswer === q.answer){ score++; feedback.style.display = "block"; feedback.style.background = "#ecfdf5"; feedback.style.color = "#166534"; feedback.innerHTML = " ✓ Correct!
" + q.explanation; } else { feedback.style.display = "block"; feedback.style.background = "#fef2f2"; feedback.style.color = "#991b1b"; feedback.innerHTML = " ✗ Not quite.
" + q.explanation; } }); var result = document.getElementById("quizResult8"); if(unanswered > 0){ result.style.display = "block"; result.style.background = "#fff7ed"; result.style.color = "#9a3412"; result.innerHTML = `

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Please answer all 8 questions before completing your mission.

`; result.scrollIntoView({ behavior:"smooth", block:"center" }); return; } var percentage = Math.round( (score / questions.length) * 100 ); result.style.display = "block"; /* ===================================== PASS ===================================== */ if(percentage >= 70){ result.style.background = "#ecfdf5"; result.style.color = "#166534"; result.innerHTML = `
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Mission Complete!

${percentage}%

You answered ${score} out of 8 questions correctly.

Great work, Money Agent! You understand that earning interest can help savings grow, while paying interest can make borrowing cost more.

You've unlocked another important money skill!`; } /* ===================================== NOT PASSED ===================================== */ else { result.style.background = "#fef2f2"; result.style.color = "#991b1b"; result.innerHTML = `
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Keep Training, Money Agent!

${percentage}%

You answered ${score} out of 8 questions correctly.

You need at least 70% to complete this mission. Review how interest works and try again.

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