Build Explanations in Science: Scaffolding That Sticks

One of the most powerful shifts I’ve made in my teaching is seeing student explanations not as an “end-of-unit assignment,” but as something that grows—little by little—throughout an investigation. Ambitious Science Teaching reminds us that kids need structured opportunities to rehearse, sketch, talk, and revise before they’re ever asked to put a polished explanation on paper.

Explanations are not a one-shot event. They are built, rehearsed, and stretched over time.

Step 1: Prethink & Prewrite

If we jump straight to “write your explanation,” we risk shutting kids down—especially our youngest learners, ELs, or students who need more processing time. Instead, we give them tools to prethink before they write:

• Storyboards: A simple three-frame sequence (beginning, middle, end) of a phenomenon. For example, instead of saying, “Explain why your shadow changes during the day,” ask first graders to sketch the sun and shadow at three different times. Then add draft words.

• Writing scaffolds: Sentence starters, idea banks, and word walls make it possible for kids to grab language they might not generate on their own.

• Strategic partnerships: Pair thoughtfully—EL students or those with IEPs benefit from working alongside a peer who models language and ideas without taking over.

Step 2: Add Evidence Without More Writing

Kids can easily drown in writing if we keep piling it on. Instead, we layer in evidence in quick, visual ways:

• Sticky notes: Students attach notes to their storyboard or draft, connecting their ideas to data from a lab or detail from a text.

• Guided questioning: A gentle “How do you know?” encourages students to link claims and evidence without shutting them down.

Step 3: Rehearse & Revise

This is where explanations start to take shape.

• Partner or small-group sharing: Students practice their draft explanations aloud, in a low-stakes way.

• Academic language rehearsal: Hearing and trying out words like because, therefore, caused by gives them confidence before writing.

• Revision time: After feedback, they refine storyboards or add more detail.

Step 4: Whole-Class Performance

Explanations need a stage. Invite students to present ideas to the whole class, but keep the focus on rehearsed explanations rather than putting them on the spot. This helps normalize science talk, makes ideas visible, and allows kids to borrow from each other’s phrasing.

Step 5: Final Product

Now the writing makes sense—students are ready to polish their ideas.

• Evidence-based writing: Explanations become stronger because they’ve been sketched, talked through, revised, and connected to data.

• Collaboration with literacy teachers: When science writing aligns with literacy scaffolds (moving from sentence → paragraph → essay), students see coherence across subjects.

Force and Motion Storyboards

In kindergarten or first grade, kids are just beginning to make sense of pushes and pulls. My Force and Motion Storyboards resource was built for exactly this purpose. Students cut out storyboard images and sequence them to show how an object moves. As they arrange pictures of rolling balls or sliding blocks, they are literally building an explanation step-by-step.

Here’s how the scaffolding cycle plays out:

• Prethink & Prewrite: Children glue their sequence and add a short sentence with support from vocabulary cards (push, pull, speed, direction).

• Add Evidence: During a toy car investigation, they explain: “The harder I pushed, the farther it went.” This extra evidence could maybe be added by a teacher at the bottom of the page.

• Rehearse & Revise: Then they practice explaining what happened using cause-and-effect phrases, ideally in pairs or small groups.

• Whole-Class Performance: A few volunteers share their storyboards with the class.

  
  

Even without heavy text demands, students are engaging in the work of scientists—observing, sequencing, explaining, and connecting evidence to ideas.

By grades 3–5, kids are ready for more layered explanations. Take an investigation into why some materials conduct heat better than others.

• Prethink & Prewrite: Students storyboard the sequence: “Hand touches spoon → heat moves → hand feels colder.”

• Add Evidence: They tape sticky notes from their data table onto their drafts: “Metal dropped the temperature by 3 degrees in 5 minutes.”

• Rehearse & Revise: In small groups, they practice saying: “The metal spoon felt colder because it pulled heat from my hand faster than the wooden spoon.”

• Whole-Class Performance: Groups present their reasoning, comparing and critiquing.

• Final Product: Students write a full paragraph explanation with claim, evidence, and reasoning.

  
  

This shows how scaffolds grow with students. Younger kids lean heavily on visuals and oral rehearsal. Older students still benefit from those supports but are pushed toward deeper reasoning, precise evidence, and structured writing.

The Big Idea

Explanations aren’t a one-time event. They’re a living process—sketched, spoken, revised, shared, and finally written. When we scaffold across these five steps, students at every grade level not only write better explanations, but also think more like scientists.