8th grade science activities

What 8th grade science looks like

Six things that turn a demo into an investigation

1. 1. A real problem with stakes the class can feel.

   “Show that mass is conserved” is a worksheet. “Prove nobody stole from the factory” is a problem.

2. 2. Apply, don't recall.

   A second round that only works with the data from the first. If the activity can be finished without the science, it isn’t a science activity.

3. 3. Group goals with individual accountability.

   The one most science classics miss: one kid zips the bag, one kid reads the scale, two kids wait for the pop. When the group shared a goal and each student answered for a part, 84% of studies found a positive effect; without both, 17% (Slavin, 1991).

4. 4. The teacher leads the thinking.

   The inquiry finding above settles it. Three questions at the balance beat a worksheet of twenty at the desk.

5. 5. A debrief where the class argues it out.

   The investigation is the setup. The argument afterward is the practice the standards name: engaging in argument from evidence.

6. 6. A way to see who did what.

   If you can’t tell which student predicted with a reason and which one copied the number, you can’t teach the practice. You can only hope for it.

If nobody predicted the number, nobody learned from it.

The sheet at the end of the next section has the sealed bag ready to run next to the balance: the role cards, the team’s mass table and atom model, the factory finding, and the tally. Get the sheet →

The sealed bag, rebuilt for 8th grade (MS-PS1-5)

Time

50 minutes. The 45-minute cut: one amount in round two, not two, and skip the re-zeroing drills; the Weigher practices once at the start.

Groups

Fours. With 30 students, seven groups of four and one of two, where the Mixer also models.

Supplies for eight teams

16 quart zip bags, a box of baking soda, a liter of vinegar, 16 small cups, balances that read to 0.1 g (one per two teams; about $15 each if the room has none), and goggles. About $6 beyond the balances.

Standards

MS-PS1-5 (use a model to describe how the number of atoms doesn’t change in a chemical reaction, so mass is conserved). The open-bag weigh is the second half of the model: the mass that “leaves” is gas, not lost.

1. 1Teach first, 10 minutesApply

   Pour vinegar on baking soda in an open cup on a balance, and let the class watch the reading drop. Ask where the mass went. Don’t answer. Name the claim the class will test: if atoms are only rearranged, the mass before and after has to match, as long as nothing escapes.

2. 2The problemStakes

   A food company’s factory line mixes two ingredients in sealed pouches and keeps finding the pouches lighter than what went in. The accountants say product is being stolen; the chemist says nothing is missing. The team owes the company a one-page finding with data: is mass lost in a sealed reaction, and where does it go when the pouch is opened? Say the stakes out loud: the finding decides whether a worker gets accused.

3. 3Four roles, one job eachAccountability

   On the sheet, and everyone signs their role’s box. Mixer and Weigher swap between rounds.

   • Mixer

     The only hands on the bag; seals it with the vinegar cup upright inside, then tips it.

   • Weigher

     Zeros the balance and reads before, sealed after, and opened after, aloud to a tenth of a gram.

   • Modeler

     Draws the atoms before and after: the same count, rearranged, with the gas leaving when the bag opens.

   • Recorder

     Keeps the mass table and the differences.

4. 4You lead the thinkingTeacher leads

   Three questions, asked at the balance: What’s your mass before, and what do you predict after? Where did the mass go when you opened the bag, in atom words? What would have to be true for mass to really disappear? The hardest part is not answering the first time a team says “the gas weighs something.” Let them prove it.

5. 5Two rounds, so the claim has to holdApply

   Round one is the sealed run. Round two is a second run with a different amount of baking soda, to test whether the sealed result holds. A team that only believed round one because the teacher said so finds out in round two whether it can predict the number on its own.

6. 6The debrief, 12 minutesDebrief

   Every team’s three masses on the board. Did any sealed bag lose mass, and if a reading dropped, what’s the explanation: a leak, the scale, or physics? What is the accountants’ mistake, in atom words? Who on your team predicted the open-bag number before it was read? Then the hard one: the bag that puffs up reads lighter, and it isn’t a leak. Who can explain it? The first question is the lesson: a dropped reading has more than one cause, and the class has to say which one it was and how it knows.

7. 7See who did whatSee who did what

   The observation sheet, four behaviors per student: predicted with an atom-level reason, measured accurately, disagreed with a reason, changed their mind when the data said to. A tally catches about half the room in one period; the bag inflating on the balance pulls every eye in the room, and that’s your moment to walk.

(The bag that puffs up reads a little lighter, and nothing got out. It’s pushing aside more air now, and that air holds it up, roughly a milligram for every milliliter it swells. Let the class find that one.)

Goggles on, every round. That line is on the sheet’s supply list.

Five more 8th grade investigations, by standard

• Our part · We make Missions

  Then the unit has somewhere to go

  Plenty of teachers rebuild these by hand every unit, and it works. A Mission is a teacher-led, whole-class simulation on a middle school standard: your class becomes the crew, the scenario is built from a unit you teach, and the only way through is using it together. The sealed bag belongs to the reactions unit, and Cold Dark Planet belongs to the waves unit. No Mission is built on the bag’s own standard, MS-PS1-5. The nearest is Escape Route, on atoms and molecules, first in the physical science table below.

  You're at the helm, not on the hook.

  Cold Dark Planet: the Mission we'd run in 8th grade

  Cold Dark Planet · Grades 7 and 8 · About 34 minutes · One device per student, plus your projector · Free with a teacher account

  

  Tractum’s star is reaching the end of its life and no longer gives the planet enough heat or light to sustain life. Dr. Zyla is working on a long-term fix, but the people of Tractum are in danger now, and she needs the crew of the Infini-D to handle it. The crew uses what it knows about waves and energy to get the planet through a bitter winter. The story plays on the projector. The work happens at seven stations (Command, Engineering, Medical, Security, Science, I.T., Operations) and in the arguments between them.

  Every student is assigned to a team, and each team’s work is themed to it, from its own information and challenge to the same problem the rest of the crew is solving. The team gives a student a role in the story and people to lean on while you move between teams. You’re at the helm, asking which wave carries more energy and what this material does to it.

  It’s built to MS-PS4-1 and MS-PS4-2: how a wave’s amplitude relates to its energy, and how waves are reflected, absorbed, or transmitted through materials. It asks that students already know how amplitude changes a wave’s energy and how light changes as it passes through different-shaped prisms, so it fits the end of the waves unit, and its Mission Guide lists a Slinky wave lab among the prep, which makes entry 6 above a head start. Tell the class it’s coming the day waves start: they’re going to need amplitude when Tractum starts freezing. The lesson prepares them. The Mission is what they’re preparing for.

  “It’s been a while since students left my period saying that was the best class ever.”

  Will it work in my room?

  Students join with a class code: no student accounts, no student email, no passwords. Chromebooks, laptops, or tablets, plus your projector. Free for teachers, no credit card. Student data is covered by COPPA and FERPA, and we signed the Student Privacy Pledge. Teach five sections of the same course? Run the Mission with each one, and every student still gets a report. On a shared cart it’s the day you have the cart, and that’s fine, as long as the class knows from the start of the unit where it’s headed. At about 34 minutes, Cold Dark Planet fits inside a 45-minute period with about 11 minutes left to talk.

  START FREE →

  Communication first, then waves, then atoms

  • The Communication MissionA version for every grade, K to 8Run this one first. It gives your class the training to run any Mission in the library.
  • Cold Dark PlanetGrades 7 and 8 · About 34 minutesA dying star, a freezing planet, and what waves can carry (MS-PS4-1, MS-PS4-2).
  • Escape RouteGrades 6 to 8 · About 34 minutesThe Mission nearest the sealed bag, on atoms (MS-PS1-1): a lab leaking toxic air, and molecules rebuilt atom by atom into something safe.

  What the report shows

  

  Every Mission produces a report for every student, built from what that student did across the whole Mission, on the skills the Mission captured. The six it can capture are Knowledge, Application, Initiative, Collaboration, Critical Thinking, and Resilience. The first two are what a test already sees. The other four are the human skills every school promises. The test shows what they know. The report shows the rest. SEE THE EVIDENCE →

  You taught it. Now find out who can use it.

  Who's behind it

  Mission.io is a research and design organization with one job: make collaborative, active learning something a teacher can run every unit instead of once a semester, and put a report in your hands when it’s over. Over a million students have run a Mission. The research behind them is funded by the National Science Foundation and the U.S. Department of Education’s Institute of Education Sciences, and Mission.io meets ESSA Level II standards, as validated by Instructure.

  8th grade science Missions by NGSS standard

  Cold Dark Planet is one. There are 13 science and engineering Missions at 8th grade, numbered 7 to 19 below, and each one is where a unit can end: waves end at Cold Dark Planet, atoms end at Escape Route, forces end at Laser Labyrinth. Every lesson finally has somewhere to go. The 6 to 8 standards are one band that each state orders its own way, so the tables group every Mission we run at 8th grade by the band’s codes, whatever year your state teaches them. Each code links to its standard on nextgenscience.org.

  Physical science (MS-PS1, MS-PS2, MS-PS4)

  The year’s home table if your state puts physical science in 8th. Three standards here have no Mission, and an investigation on this page teaches each one; Escape Route works on the atoms the sealed bag’s model counts.

  Physical science Missions at 8th grade, by NGSS code, with the three standards that have no Mission.

  #Number	The standard	Mission	MinutesMin
  7	MS-PS1-1 Model the atoms in simple molecules, then rebuild toxic air into something safe (grades 6 to 8)	Escape Route	34
  8	MS-PS1-4 Heat in or heat out: how thermal energy changes particle motion and a substance’s state (grades 6 to 8)	The State of Things	40
  9	MS-PS2-2 A change in motion depends on the forces and the mass (grades 5 to 8). On this page: 5. Marble ramp.	Laser Labyrinth	32
  10	MS-PS4-1, MS-PS4-2 A wave’s amplitude and its energy; waves reflected, absorbed, or transmitted (grades 7 and 8). On this page: 6. Slinky waves.	Cold Dark Planet	34
  	MS-PS1-2 Properties before and after two substances interact show whether a chemical reaction happened. On this page: 2. Elephant toothpaste.	No Mission
  	MS-PS1-5 Atoms rearrange in a chemical reaction and none are lost, so mass is conserved. On this page: 1. The sealed bag.	No Mission
  	MS-PS2-1 Newton’s third law, applied to a design problem where two objects push on each other. On this page: 4. Balloon rocket on a string.	No Mission

  Life science (MS-LS1, MS-LS2)

  Three, for the states that teach some life science in 8th. Chloroplast Chaos is the other Mission on this page made for grades 7 and 8 alone.

  Life science Missions at 8th grade, by NGSS code.

  #Number	The standard	Mission	MinutesMin
  11	MS-LS1-3 How cells build tissues, organs, and the systems that keep a body alive (grades 5 to 8)	System Shutdown	34
  12	MS-LS1-6 How photosynthesis cycles matter and moves energy through living things (grades 7 and 8)	Chloroplast Chaos	31
  13	MS-LS2-2 Competition, predation, and partnership: the same patterns of interaction in every ecosystem (grades 3 and 6 to 8)	Ecosystem Patterns	39

  Earth and space (MS-ESS1, MS-ESS2)

  Three, and Storm Front at 16 minutes is the shortest Mission on the page.

  Earth and space Missions at 8th grade, by NGSS code.

  #Number	The standard	Mission	MinutesMin
  14	MS-ESS1-3 Size, distance, and other scale properties of planets and moons, worked from data (grades 6 to 8)	Encrypted Escape	30
  15	MS-ESS2-2 Plate boundaries, earthquakes, and volcanoes as evidence of a surface that changes (grades 5 to 8)	Mount Katastrofi	24
  16	MS-ESS2-5 Warm and cold front data as evidence for how the weather changes (grades 6 to 8)	Storm Front	16

  Engineering design (MS-ETS1)

  Three on the band’s engineering design standards. Spine-Backed Globster carries three of the band’s four engineering codes in one story, plus two ecosystem codes. The 8th grade engineering activities page maps these standards with the design challenges that teach them.

  Engineering Missions at 8th grade, by NGSS code.

  #Number	The standard	Mission	MinutesMin
  17	MS-ETS1-1, MS-ETS1-2, MS-ETS1-3, MS-LS2-4, MS-LS2-5 Fight an invasive species in a marine ecosystem: set the criteria, test the fixes, combine the best (grades 6 to 12)	Spine-Backed Globster	36
  18	MS-ETS1-2 Compare plans for removing infected tissue by how well each meets the criteria (grades 6 to 9)	Infection	34
  19	MS-ETS1-3, MS-ETS1-2, 3-5-ETS1-1, 3-5-ETS1-2 Weigh ways to protect three islands from a tsunami against criteria and constraints (the grades 5 to 8 build)	Tsunami	33

  START FREEMISSION BRIEF →

  Free teacher account, no card. Start with the Communication Mission, marked Start here in your library, then the Mission for your unit, each after its 5-minute Teacher Preview.

  Also at this grade

  The 8th grade STEM activities page lists the math, technology, and career Missions; the 8th grade engineering activities page rebuilds a build of its own; and the Collaboration and Critical Thinking Missions live on the 8th grade collaboration activities and 8th grade critical thinking activities pages.

Questions 8th grade science teachers ask

I have a 45-minute period. Which of these fit?

The sealed bag runs 50 minutes; the 45-minute cut runs one amount in round two and skips the re-zeroing drills, with the Weigher practicing once at the start. Most Missions fit one period with time left to talk, and three on this page run 30 minutes or less: Storm Front (16 minutes), Mount Katastrofi (24), and Encrypted Escape (30).

Which NGSS standards do these 8th grade activities map to?

NGSS sets middle school as one 6 to 8 band, and each state decides what lands in 8th. This page follows the common order, physical science in 8th: the sealed bag is MS-PS1-5, and the five run MS-PS1-2, MS-PS2-1, MS-PS2-2, and MS-PS4-1, with Mentos and soda as the one no standard claims. MS-PS1-5, MS-PS1-2, and MS-PS2-1 have no Mission. The tables map every 8th grade Mission across physical science (MS-PS1, MS-PS2, MS-PS4), life science (MS-LS1, MS-LS2), Earth and space (MS-ESS1, MS-ESS2), and engineering (MS-ETS1).

A sealed bag lost mass. Did the lab fail?

Not necessarily. A leak at the zip, a drifting balance, and the bag itself can each lower the reading. A bag that puffs up pushes aside more air, and that air holds it up, so it reads lighter with nothing lost, roughly a milligram for every milliliter it swells. Sorting out which one happened is the best part of the debrief. A team that can name the cause has done more science than a team that matched to the tenth of a gram and can’t say why.

Is Mentos and soda a chemical reaction?

No. It’s a physical change: the gas was already in the soda, and no new substance forms. That’s why it sits on this page as the contrast to the sealed bag, where the class has to show that a new substance did form and the mass still didn’t change.

How do I grade the sealed-bag lab fairly?

Grade the finding and the behaviors. The factory finding is one grade: is mass lost in a sealed reaction, and where does it go when the pouch opens, in atom words, with the three masses as evidence. The four-behavior tally over two or three investigations is the other. A team that got the right number with no atom-level reason shows up as a weak finding, and now you can say why.