CER Mystery Images

What Happened Here?

Ten photos. One question each. Students observe visible clues, consider possible inferences, and build a CER explanation.

Use it your way

Next and the arrow keys move through the slides. Every mystery has a Full screen button. One-page student worksheets are available through VST Teacher Membership. Use Choose worksheets to select only the mysteries you want.

Whole classProject one photo, give quiet looking time, then talk through the five questions together.

Small groupsEach group takes a different mystery, then presents to the class, or groups swap photos and compare claims.

IndividualUse the worksheet picker to choose specific mystery worksheets for independent CER work.

Warm up or stationsUse one image as a bell ringer, or place one mystery at each station.

Or invent your own. Any approach that gets students looking closely and arguing from evidence works.

How observation and inference fit into CER

An observation describes something students can directly see. An inference is an idea about what those observations might mean. Students can consider several inferences, turn the best-supported one into a claim, select relevant observations as evidence, and explain the connection in their reasoning.

The same five questions for every photo

ObserveWhat do you notice? Describe only what you can directly see before explaining it.
ClaimWhat is your answer to the question? Your best-supported inference may become your claim.
EvidenceWhich observations support your claim?
ReasoningWhy does that evidence support your claim?
Check itWhat other explanation could fit the same evidence?

The thinking path

Observations → possible inferences → claim → evidence → reasoning. An observation becomes evidence when a student selects it because it supports the claim.

Wrap up

Talk about

Did your first inference become your final claim, or did the evidence cause you to revise it?
Which observations became evidence for your claim?
Which photo supported more than one reasonable explanation?
What additional evidence would help you decide?

Why it matters

Sometimes scientists watch an event as it happens. Other times the event is too long ago, too slow, or already over, and nobody could have watched it. That is when scientists read the traces the event left behind and argue for the explanation the evidence supports best.

Quick check for a strong CER

The claim answers the question and is supported by the observations.
The evidence comes from the photo and is relevant to the claim.
The reasoning explains the link instead of repeating the evidence.
Other explanations were considered and compared with the evidence.