The purpose of this activity is for students to practice subtracting fractions with unlike denominators. The structure of this activity is identical to the first activity in the previous lesson, except that students are calculating differences instead of sums. Monitor for students who:

• Try to make the first fraction in each pair as large as they can and the subtracted fraction as small as they can.
• Find a common denominator for all 4 differences in order to add them together.

While playing the game, students may find that they have a smaller fraction as the minuend and a larger fraction as the subtrahend. There are several ways students could navigate this situation, one of which is to switch the order of the fractions.

• “¿Qué estrategias les ayudaron mientras jugaban ‘La mayor diferencia’?” // “What strategies were helpful as you played Greatest Difference?” (I tried to make the first fraction in each pair as large as possible and the second fraction in each pair as small as possible.)
• “¿Cuál es la mayor diferencia posible entre las fracciones de este juego? ¿Cómo lo saben?” // “What is the greatest difference possible between fractions in this game? How do you know?” ( , because  is the greatest number on the spinner and is the least.)
• “¿Alguien obtuvo la fracción  ?” // “Did anyone get as one of their fractions?” 

The purpose of this activity is for students to practice subtracting fractions with unlike denominators. This activity has the same structure as the previous activity, except that students are looking for the least difference rather than the greatest difference, and this time they are given all of the numbers at once rather than spinning them one at a time. Some strategies to monitor for include:

• Trying to get a difference of 0 using equivalent fractions.
• Trying to make all of the fractions as small as possible, that is, using a similar strategy to the sum game when they tried to get the least possible sum.

While playing the game, students may find that they have a smaller fraction as the minuend and a larger fraction as the subtrahend. There are several ways students could navigate this situation, one of which is to switch the order of the fractions.

• “¿Qué estrategias les ayudaron mientras intentaban encontrar la menor diferencia?” // “What strategies were helpful as you tried to find the least difference?” (I tried to choose equivalent fractions so that I could get a difference of 0. I tried to choose small fractions so the difference would also be small.)
• “¿Alguien escogió números que hicieron que la segunda fracción fuera mayor que la primera?” // “Did anyone choose numbers that made the second fraction greater than the first?” (Yes.)
• “¿Qué hicieron en ese caso?” // “What did you do?” (I switched the order of the fractions so that I could subtract.)
• “¿Alguien logró obtener un total de 0?” // “Was anyone able to get a total of 0?” (No, because I could only get a difference of 0 in one expression, not both. I could get some equivalent fractions with sixths, or fourths, thirds, or halves but there was nothing I could do with fifths. If I put the 5 in the numerator I can’t make an equivalent fraction.)