Delaware Grade 7 Math

Work through the example

An invented temperature record starts at 5°C and ends at −3°C. Find the signed change and explain how far apart the two readings are on a number line.

Connect the model and calculation

Signed change is ending temperature minus starting temperature: −3 − 5 = −8 degrees Celsius. The negative result describes a decrease. On a number line, moving from 5 to 0 accounts for five degrees and from 0 to −3 accounts for three more, so the distance between the readings is eight degrees. Distance is |−3 − 5| = 8. The same observations can therefore be described as a change of −8 degrees or a drop of 8 degrees.

Understand an incorrect answer

An answer of −2 adds the two readings instead of finding the change. An answer of +8 correctly gives the distance but not the direction of this signed change. Ask which value is the start and which is the end before writing a subtraction. A colder final temperature does not imply the temperature has dropped by only three degrees; that number describes the final reading relative to zero.

Transfer the idea to another example

Reverse the record, starting at −3°C and ending at 5°C. The signed change becomes 5 − (−3) = 8, while the distance remains eight degrees. Explain subtraction of a negative as adding its opposite. Then keep the end at −3°C but start at −7°C: the change is +4 because the reading rises. Choose a related integer worksheet and require an interpretation of the sign as well as an arithmetic answer.

Selected Delaware Grade 7 references

The Delaware mathematics standards directory links the Common Core publisher. Delaware’s standards regulation, section 1.1.1.1, identifies adoption for the 2010–11 school year. Use the adopted document alongside the school’s instructional plan. These labels summarize the activity’s focus; read the complete expectations and mathematical practices in the publisher’s mathematics document.

Sources checked October 5, 2026. This selected activity is an entry point for instruction, not a complete curriculum checklist.

Connect the explanation with practice

Use the lesson, worksheet, and quiz directory to choose a related skill. The existing resource links remain available; open each activity’s directions to understand its timer, tools, question count, and scoring.

Grade 7 is within Delaware’s Smarter Balanced mathematics testing range. The linked learning resources have their own directions and scoring; a practice score does not establish an official state performance level. Read Delaware’s official summative assessment overview.

Keep one example of the student’s reasoning with the practice result. Choose a smaller model, a related question, or a new context according to the difficulty revealed in the worked activity.