Supported pathway · Week 6 of 6
Systems, Models & Scientific Reading
Culminate the bridge by reading science as evidence, building causal system models, distinguishing feedback from simple cause-and-effect, evaluating source claims, and integrating data across matter, energy, life science, and scientific practices.
Learning objectives
- Define a scientific system using components, interactions, boundary, inputs, outputs, and state variables
- Construct causal models with explicit mechanisms and direction
- Distinguish negative feedback, positive feedback, and one-way causal chains
- Read scientific prose, figures, tables, and captions as different evidence forms
- Separate source-supported statements, paraphrases, and student inferences
- Evaluate authority, evidence, relevance, date/context, and limitations of a scientific source
- Cite a source sufficiently for another reader to locate it
- Integrate multiple evidence types into a defensible scientific explanation
- Revise a model when new evidence conflicts with it
Do not invent observations, citations, authors, measurements, or conclusions. If evidence is unavailable, say that the claim remains uncertain. Uncertainty is scientifically preferable to fabricated certainty.
1 · Define the system before explaining it
A system model identifies what is inside the boundary, what lies outside it, relevant components, interactions, inputs, outputs, and variables that can change. Different boundaries can be useful for different questions.
Model a potted plant first as the system, then model the entire room containing the plant as the system. For each boundary identify matter inputs/outputs, energy transfers, and one variable that could be monitored.
2 · Causal arrows need mechanisms
An arrow labeled “A → B” should mean more than “A and B are related.” Scientific causal models state how a change in A could produce a change in B and under what conditions.
Improve these weak models: “sunlight → plant growth,” “exercise → breathing,” and “temperature → dissolving.” Add intermediate mechanisms, measurable variables, and at least one condition that could alter the relationship.
3 · Feedback is a loop
In negative feedback, a response tends to reduce the original deviation from a regulated condition. In positive feedback, a response amplifies or reinforces a change for a period. A simple sequence A → B → C is not feedback unless a later effect returns to influence an earlier part of the system.
For each scenario—room thermostat, microphone near a speaker, body temperature regulation—draw a causal model and identify whether it contains negative feedback, positive feedback, or neither. Explain where the loop closes.
4 · Read science in layers
Scientific communication often combines prose, diagrams, tables, graphs, captions, equations, and references. Do not assume the prose and figure say exactly the same thing. Read each evidence form independently before integrating them.
Use this sequence with a supplied scientific passage or open educational science source: READ → ANNOTATE → EXTRACT EVIDENCE → INTERPRET FIGURE/TABLE → CONNECT MECHANISMS → QUESTION → MODEL → CITE.
Record three source-supported statements, one interpretation, one question, and one model revision.
5 · Supported, paraphrased, inferred
Mark scientific notes so you know where ideas came from: S = directly supported by the source; P = paraphrased from the source; I = your inference or synthesis. A citation identifies a source; it does not automatically make an inference correct.
Take five statements from your scientific reading notes and label each S, P, or I. For every I statement, identify which evidence supports it and one alternative interpretation if reasonable.
6 · Evaluate the source, not just the URL
Ask: Who produced this information? What evidence is presented? Is the source relevant to the question? Is date/context important? Are methods or references visible? What limitations or conflicts are acknowledged? A government, university, museum, scientific society, open textbook, or peer-reviewed source can be useful, but authority does not remove the need to inspect evidence.
Compare two supplied sources addressing the same scientific topic. Evaluate authority, evidence, relevance, currency/context, transparency, and limitations. Decide which source is stronger for the specific question and explain why.
7 · Citation is scientific traceability
A useful citation allows another learner to locate the evidence. Record enough information for the source type: author or responsible organization, title, section/page when useful, publication/site, date when available, location/URL when permitted, and access date for changing web resources.
Create a citation record for the scientific source used above. Exchange it with another learner or reviewer. Could that person locate the exact evidence without guessing? Revise if necessary.
8 · Integrate evidence without flattening it
Different evidence can support different parts of an explanation. A table may establish a measured trend; a diagram may represent a proposed mechanism; prose may summarize established knowledge. Preserve those roles instead of treating every source as identical proof.
Combine one table, one figure/model, and one prose source into a single explanation. For each claim identify which evidence supports it, whether the support is direct or inferential, and one remaining uncertainty.
Bridge Culminating Performance Task · The Changing System
A fictional sealed terrarium is moved from a stable environment into brighter light for several hours each day. Over a week, supplied data show changes in internal temperature, humidity, gas concentrations, and plant growth. Students receive a data table, two graphs, a system diagram, and a short scientific reading.
- Define the system boundary and relevant components.
- Identify matter inputs/outputs and energy transfers.
- Extract at least four direct quantitative observations.
- Calculate one interval rate and one percent change.
- Construct a causal model with at least six meaningful nodes.
- Identify any plausible feedback loop and explain where it closes.
- Use particle/cell/organism reasoning where appropriate.
- Tag at least three statements S/P/I.
- Cite the supplied reading for one source-supported mechanism.
- Identify one limitation in the data or model.
- Construct a competing explanation for one pattern.
- Propose the next measurement most useful for distinguishing the explanations.
- Revise the model after receiving one new piece of conflicting evidence.
- Write a final CER explanation that states what is known, inferred, and still uncertain.
Week 6 mastery evidence
Complete the ten-item check. 8/10 or higher plus reasoning corrections records Week 6 mastery. Completion of Week 6 does not by itself release Unit 1; the separate Science Foundations Mastery Assessment verifies bridge readiness across all six weeks.
- Define a scientific system boundary and explain why boundary choice matters.
- Distinguish a causal mechanism from a correlation.
- Distinguish negative feedback from positive feedback.
- Explain why a one-way causal chain is not necessarily feedback.
- Extract one direct observation from a supplied scientific figure or table.
- Distinguish source-supported evidence from student inference.
- Name three criteria for evaluating a scientific source.
- Create a traceable citation record for a supplied source.
- Integrate two evidence types into one qualified scientific claim.
- Describe the scientifically appropriate response when new evidence conflicts with a model.
NAIB Week 6 record
Record Systems, Models & Scientific Literacy: mastery percentage, stable skill IDs, attempts, correction status, strengths, and refresh priorities. Preserve the distinction among Course Mastery, Retention, Refresh, and Readiness.
Compare how you approached scientific evidence at the beginning of Week 1 with how you approach it now. Identify one reasoning habit, one quantitative habit, and one modeling/reading habit that changed.