Skip to content
LessonPrint

Weighed Before, Weighed After is a free printable Grade 5 science worksheet on measuring to show the total weight of matter is conserved, aligned to Common Core standard 5-PS1-2. It prints 5 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two pupils in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.

Set 20 of 25 · the same problems every time you open this link.

Next setLesson plan

One paper per pupil

12345678910111213141516171819202122232425

Set 1 has all 25 in a single PDF. All 25 sets ask different questions.

Weighed Before, Weighed After

5-PS1-2

NameDate

Read the record, then answer the questions.

1.Read the record, then answer the questions.

Weighed Before and Weighed After

Masses recorded on the same balance, before and after four changes. MASS BEFORE AND AFTER Sugar stirred into water, sealed jar ... 254.0 g then 254.0 g Ice melted in a sealed bag ............ 118.6 g then 118.6 g Vinegar and soda in a SEALED jar ...... 201.3 g then 201.3 g Vinegar and soda in an OPEN jar ....... 201.3 g then 197.8 g The same balance was used for every reading.

  1. 1. What was the mass after sugar was stirred into water?
  2. 2. What happened to the mass in every sealed container?
  3. 3. Why did the open jar lose mass when the sealed one did not?
  4. 4. What claim does this record support?
2.A sealed jar of vinegar and soda weighs the same before and after fizzing. What does that show?
  • A.The balance was wrong
  • B.No matter was lost; the gas is still inside the jar
  • C.Matter was destroyed
3.Ice melts in a sealed bag. What should the mass do?
  • A.Stay exactly the same
  • B.Rise, because water is heavier
  • C.Fall, because liquid is lighter
4.Why is the sealed jar the fair test of conservation?
  • A.Nothing can leave, so the balance measures all the matter
  • B.Open jars are inaccurate
  • C.Sealed jars are heavier
5.Why use the same balance for every reading?
  • A.Balances are all identical
  • B.So a difference between readings is a real difference in mass
  • C.To save time

LessonPrint · 5-PS1-2 · Set 20 · free to copy for classroom use

Answer key — Weighed Before, Weighed After

Set 20. Prints on its own sheet.

  1. 1.1. 254.0 g, the same as before. 2. It stayed exactly the same before and after. 3. Gas escaped from the open jar, and the sealed jar kept it inside. 4. The total mass of matter stays the same through a change, when nothing can escape.
  2. 2.No matter was lost; the gas is still inside the jar
  3. 3.Stay exactly the same
  4. 4.Nothing can leave, so the balance measures all the matter
  5. 5.So a difference between readings is a real difference in mass

More practice for 5-PS1-2

Measure and graph to show that weight is conserved when matter changes.

Teaching this next? Weighed Before, Weighed After is the 60-minute plan for it, with the misconceptions to expect.

All Grade 5 worksheets

Last reviewed 2026-09-05. Aligned to 5-PS1-2 of the Next Generation Science Standards.