Teaching high school chemistry often feels like teaching math in disguise. If you’ve ever thought, “I didn’t realize I signed up to be a math teacher!”—you’re not alone. Using mathematics and computational thinking is even a core science practice in the NGSS and other 3-dimensional approaches, yet many students struggle with math-related tasks in chemistry.
With national test scores showing students falling behind in math, how do we teach essential chemistry concepts—like predicting ion charge—without turning into full-time math teachers? The answer: developing and using models!
In this article, I’ll walk you through an engaging, NGSS-aligned ions activity that makes using mathematics and computational thinking more accessible by leveraging the power of models. You’ll learn exactly how to guide students through visualizing ion formation, predicting charges, and applying periodic table patterns—all while reinforcing active, inquiry-based learning.
Read on (or watch) to explore how to make math-heavy chemistry lessons feel intuitive, engaging, and student-centered.
Table of contents:
- Key Features of This NGSS Ions Activity
- Required Prior Knowledge For This Ions Activity
- Lesson Framework: A 5-Part Structure for Success With This NGSS Ions Activity
- Empowering Students with A Student-Centered Ions Activity
- More Engaging, NGSS-Aligned Chemistry Lessons Like This
- Apply These Inquiry-Based Strategies to Any Science Content
Key Features of This NGSS Ions Activity
Teaching students how to predict ion charges is often a struggle because it requires them to integrate math, periodic trends, and atomic structure all at once. Without a student-centered approach designed for active learning, students either memorize charges with no real understanding or get confused by the math, unable to apply it meaningfully.
This NGSS-aligned ions activity eliminates those barriers by leveraging the development and use of models first, so students build a conceptual foundation before working with the numbers. It’s designed to make mathematics and computational thinking feel like a natural part of the learning process rather than an overwhelming obstacle.
Here’s what makes this lesson work:
Developing and using models comes first — Not Memorizing
Too often, students are given “rules” for ion charges without ever understanding why those rules exist. The ions activity in this inquiry-based chemistry lesson flips that approach by having students:
- build neutral atoms using Bohr models so they can see electron arrangement.
- apply the octet rule in a manipulative way, rather than being told which elements gain or lose electrons.
- compare atomic structures before and after ionization, reinforcing the cause-and-effect relationship between stability and charge.
Why This Works:
Students aren’t just hearing about ion formation—they’re seeing it unfold. The octet rule isn’t introduced as an arbitrary fact, but as a driving force behind why atoms gain or lose electrons. By making stability the focus, this lesson creates a logical path for students to follow, rather than expecting them to memorize disconnected facts.
Using Mathematics and Computational Thinking Becomes Intuitive, Not Intimidating
One of the biggest hurdles in teaching chemistry is that students struggle with math—especially those with special education accommodations or weak foundational skills. Many chemistry teachers (myself included) have thought, “I didn’t realize I was signing up to be a math teacher!”
This lesson prevents math from being a roadblock by introducing it after students have developed a conceptual understanding. Rather than jumping into using mathematics and computational thinking, students:
- observe patterns in electron loss and gain using models.
- count protons and electrons in real examples before abstracting the process.
- use a structured artifact to compare the structural details of neutral and charged atoms, making the net charge calculation feel obvious rather than forced.
Why This Works:
Many students—especially those who struggle in math—need something tangible before they can engage with numbers. This lesson bridges that gap by ensuring that every mathematical concept is first explored through modeling and visualization. Then, using mathematics and computational thinking isn’t the challenge—it’s simply the natural next step.
An NGSS Ions Activity With All 3-Dimensions
This lesson is fully aligned to NGSS HS-PS1-1 and the Pennsylvania STEELS standard 3.2.9-12.A, making it a high-impact way to incorporate 3-dimensional learning into chemistry instruction. Whether or not you are required to align to the NGSS and similar standards, the ions activity in this lesson naturally supports the following science and engineering practices and cross-cutting concepts in addition to using mathematics and computational thinking:
Science & Engineering Practices:
- Developing and Using Models
- Students construct Bohr models to visualize how atoms gain or lose electrons to form ions, reinforcing the connection between valence orbital structure and charge.
- Analyzing and Interpreting Data
- As students examine trends in ion formation, they recognize consistent charge patterns across groups on the periodic table, helping them move beyond memorization to meaningful pattern recognition.
- Engaging in Argument from Evidence
- Students use their observations and data to explain why specific elements form certain ions, supporting their conclusions with evidence from their models and the periodic table.
Cross-Cutting Concepts:
- Patterns
- Students predict ion charges by identifying trends in electron gain and loss across element groups, reinforcing how periodic table structure reflects atomic behavior.
- Cause and Effect
- The lesson emphasizes stability as the driving force behind ionization, helping students see how atoms adjust electron configurations to achieve a stable octet.
- Scale, Proportion, and Quantity
- Students work with protons, electrons, and net charge calculations, developing a quantitative understanding of how electron transfer impacts an atom’s overall charge.
- Systems and System Models
- Ion formation is explored within the broader framework of atomic structure and chemical reactivity, reinforcing how chemistry operates as an interconnected system rather than isolated facts.
Why This Works:
Many teachers struggle with how to implement NGSS in a way that feels meaningful. This lesson directly integrates science practices and crosscutting concepts without adding unnecessary complexity—making NGSS alignment practical, not just theoretical.
Built for Real Classrooms: Adaptable, Structured, and Student-Centered
Cumulative & Scaffolded
This lesson fits seamlessly into a chemistry curriculum, building on prior knowledge of Bohr models, electron configurations, and the octet rule. It also prepares students for later concepts like ionization energy and the periodic law.
Flexible for Differentiation
Whether your students need extra structure or more open-ended inquiry, this lesson allows for multiple entry points, making it accessible to various learning levels.
Practical, Inquiry-Based, and Engaging
The structured five-part lesson design ensures that students actively engage in learning rather than passively receiving information.
Designed with Teachers in Mind
Every aspect of this lesson is designed to reduce student misconceptions, eliminate rote memorization, and provide a clear instructional path that makes complex concepts more accessible—especially for students who typically struggle with math-heavy concepts.
Required Prior Knowledge For This Ions Activity
Before diving into this NGSS-aligned ions activity, students should have a solid foundation in atomic structure and electron behavior, as these concepts directly influence their ability to understand ion formation. This lesson builds on prior knowledge of Bohr’s model, electron configurations, and the octet rule, helping students transition from basic atomic structure to a deeper understanding of periodic trends and chemical reactivity.
The Periodic Table as a Predictive Model
Students should already be familiar with how the periodic table organizes elements and why its structure provides valuable information about atomic behavior. In this lesson, they’ll be using the periodic table as a model to predict the properties of elements, specifically how electron arrangements in the outermost energy level determine an atom’s likelihood of gaining or losing electrons.
Bohr’s Model of the Atom
Understanding the Bohr model is crucial because students will be using it throughout this ions activity to model electron arrangements, predict how atoms will form ions, and provide support for using mathematics and computational thinking to determine ion charge. They should be comfortable with:
- identifying energy levels and placing electrons accordingly.
- recognizing that the outermost energy level (valence shell) determines an atom’s reactivity.
- differentiating between core electrons and valence electrons.
Schrödinger’s Model & Electron Configurations
While Bohr’s model provides a simple visualization, some students may also be familiar with Schrödinger’s model and electron configurations. This understanding can be helpful when discussing why atoms gain or lose electrons, but it is not required for all learners—especially if they are still working through fundamental atomic concepts.
The Octet Rule as a Driving Force for Ion Formation
The octet rule is the most essential prerequisite for this lesson. Students must understand that:
- atoms “seek” stability by having a full outer shell of electrons (usually eight).
- metals tend to lose electrons to achieve an octet, forming positive ions (cations).
- nonmetals tend to gain electrons to achieve an octet, forming negative ions (anions).
Since the ions activity in this lesson further explores ion formation as a consequence of the octet rule and sets the stage for using mathematics and computational thinking, students must have a working knowledge of this principle before engaging in the activity. If students have been introduced but aren’t quite secure, the modeling portion of this inquiry-based activity could provide an additional opportunity to review and apply those core ideas.
How This Prior Knowledge Supports the Lesson
This background ensures that when students begin manipulating atomic models and predicting ion charges, they understand the reasoning behind electron movement instead of just memorizing charge values. Without this foundation, students may struggle to see the cause-and-effect relationship between valence electron changes and charge formation—one of the key insights this lesson aims to develop.
That said, this lesson is highly adaptable! If students need extra support, components of the activity can be scaffolded or modified to reinforce the octet rule and Bohr model concepts before moving forward with more advanced applications.
Lesson Framework: A 5-Part Structure for Success With This NGSS Ions Activity
This NGSS-aligned ions activity is designed to guide students through inquiry, modeling, and using mathematics and computational thinking in a structured yet flexible way. The lesson follows a five-part framework that ensures students build conceptual understanding before applying math, analyze real patterns before drawing conclusions, and engage in active learning rather than passive memorization.
Here’s a high-level overview of how the framework unfolds:
Review & Preview: Activating Prior Knowledge Leading To Ions
Every lesson starts with a Review and Preview, which acts as a bell ringer or warm-up to activate and integrate prior knowledge. In this case, students revisit the octet rule and previous models to mentally prepare for new learning. This step ensures that students don’t see ion formation as an isolated concept—it’s part of a larger pattern that connects to their existing understanding of atomic structure. For more detail on delivering this portion of the lesson, check out the article I posted about the related octet rule lesson.
Learning Intentions & Success Criteria: Clarifying NGSS Goals for ThE Ions Activity
Before diving into new material, students are introduced to learning intentions and success criteria that clearly define:
- The “why” and “what” of the lesson
- Students understand why they are learning to predict ion charges and how they’ll apply their understanding.
- Actionable goals
- Some success criteria focus on student engagement in activities, while others emphasize demonstrating understanding in assessments.
- A structured path to mastery
- Students see where the lesson is leading them, making it easier to stay engaged and take ownership of their learning.
Inquiry-Based Learning Activity: Using Models to Teach Charge Formation
The core of this lesson is an interactive, technology-driven simulation where students actively explore ion formation rather than being told how it works. This visual, inquiry-based approach allows students to:
- build and manipulate atom models to observe how electron gain/loss changes charge.
- populate a structured artifact outline, collecting and organizing information like scientists do.
- use real-world data analysis techniques, mimicking text-dependent analysis, but with numbers and visual models instead of words.
This approach ensures that students aren’t just passively watching a demonstration—they’re engaging with the data, uncovering patterns, and constructing their own understanding.
Manipulating Atomic Models
Using the simulation, students can build neutral atoms using protons and electrons. They are limited to building atoms up to neon (atomic number 10), which keeps the focus of this ions activity on fundamental charge patterns and prevents overwhelming them with excessive complexity. Once each neutral atom is constructed, students only need to adjust the number of electrons in the valence orbital until the symbol matches what is listed on their artifact outline. When they match, students will know that they’ve modeled ionization for that atom correctly.
The instructions provided for this task are intentionally open-ended—they offer enough guidance for students to work through the process, but they aren’t so detailed that students can simply follow steps without thinking. This allows for differentiation based on student ability. If students need more structure, additional scaffolding can be added; if they are ready to work more independently, they can navigate the process without extensive hand-holding.
Completing The Artifact Outline
As students build atoms in this ions activity, they also fill out an artifact outline designed to expose patterns in atomic structure and ion formation. The outline prompts them to:
- identify the location of each element on the periodic table, paying special attention to group numbers.
- list the number of protons and electrons for each neutral atom.
- adjust the valence electron count to form a stable octet and document the final electron total in the ionized atom.
When I deliver this lesson in my classroom, students have already worked with similar models to learn the octet rule, and this activity helps transition from conceptual understanding — the octet rule is reasoning — to practical application, their outcomes provide evidence. The periodic table is used as a predictive tool, connecting theory to real observable trends.
What makes this approach so effective is that students aren’t just told that certain elements form specific ions—they see it happen. Through active engagement with the model, they begin to recognize that elements in the same groups follow consistent charge patterns, reinforcing the predictive power of periodic trends.
The challenge related to using mathematics and computational thinking is revealed when students translate these observations into charge notation. The technology tool they’re using provides an additional layer of simplified, visual aids; plus and minus symbols that allow students to directly compare proton and electron counts are provided as changes to the atomic models are made. This is critical because many students struggle with the idea that losing an electron results in a positive charge and gaining an electron leads to a negative charge—a concept that contradicts their early math education, where subtraction is depicted using a negative symbol (-) and means “loss” while addition is depicted using a positive symbol (+) and means “gain”.
By the time they complete this NGSS ions activity, students don’t just know that sodium forms Na⁺ and chlorine forms Cl⁻—they understand why.
Data-Driven Analysis: Identifying Ion Patterns And using Mathematics and Computational Thinking
Once students have completed the simulation and gathered their data, they move into the structured data analysis of their artifact outline where they:
- examine trends in ion charges across element groups.
- look for patterns in electron gain/loss and periodic table placement.
- discuss and justify their conclusions using evidence from their models.
This critical thinking step reinforces scientific reasoning and helps students connect their observations to broader chemistry concepts like periodic trends and charge predictability.
Examining Trends And Looking For Patterns In Ion Charges
At this point in the lesson, using mathematics and computational thinking becomes more explicit and is thoroughly reinforced.
Some guided questioning prompts them to compare their recorded values for protons and total electrons before and after ion formation. They take specific note of how many electrons each atom gained or lost to achieve its octet and begin calculating net charge by subtracting the total number of electrons in each ion from its total number of protons.
For example, when working with lithium, they see that the neutral atom starts with three protons and three electrons. After losing one electron to satisfy the octet rule, lithium now has three protons and only two electrons. On the other hand, fluorine starts with nine protons and nine electrons, but after gaining one electron to complete its octet, it now has ten electrons. Both of these examples provide opportunities to teach students yet another problem-solving strategy using mathematics and computational thinking — to subtract the total number of electrons from the number of protons in each atom. This will automatically result in the correct sign and the correct magnitude of the ion charge. The additional model-based activity might be necessary to cement their understanding of this way of using mathematics and computational thinking to determine ion charges.
Using Evidence To Argue Conclusions
To ensure everyone in the class is proficient with using mathematics and computational thinking in the context of determining ion charge, students can engage in a guided discussion where they must argue from evidence—a crucial NGSS science practice. Instead of simply stating, “Lithium forms Li⁺1 because that’s what the periodic table says,” they are expected to justify their conclusions based on their observations.
By explaining their reasoning in their own words, students reinforce their understanding of the cause-and-effect relationship behind ion formation:
- “Lithium forms a +1 ion because it has one valence electrons that it needs to lose to achieve stability.”
- “Fluorine forms a -1 ion because it only needs to gain one electron to complete its octet.”
Some students will immediately recognize the shortcut rule: for metals, the group number equals the ion charge (+1 for Group 1, +2 for Group 2, etc.). For nonmetals, the charge is 8 minus the group number (so Group 7 elements form -1 ions, Group 6 elements form -2 ions, etc.).
This final analysis piece is what elevates the activity from simple computation to true understanding. By the end of this process, students no longer see ion charge as random numbers to memorize—they see it as a predictable pattern driven by electron behavior and made easy using patterns evidence throughout the periodic table.
Skill Practice & Application: Solidifying Understanding
The lesson culminates in targeted skill practice, ensuring that students:
- apply their learning through guided problem-solving activities.
- engage in argument from evidence by explaining and justifying charge predictions.
- extend their understanding with additional practice opportunities.
Because this lesson integrates multiple science practices, it can take two or even three class periods to fully implement. However, this time investment is critical—it allows students to deeply engage with the material, develop confidence in their understanding, and move beyond rote memorization to meaningful application.
Empowering Students with A Student-Centered Ions Activity
Why It Works
This NGSS-aligned ions activity—starting with observational modeling, moving into guided analysis, and ending with pattern recognition and justification—mirrors the process of scientific discovery. Students don’t start with rules; they uncover them through hands-on experimentation and structured reasoning, fostering deeper understanding and long-term retention.
Rather than treating the periodic table as a static list of facts, this activity transforms it into a powerful predictive tool, helping students explain and anticipate ion formation with confidence. Through the integration of models, inquiry-based exploration, and using mathematics and computational thinking, students engage with the content in a way that makes abstract concepts tangible and meaningful.
Delivery Options
Because this NGSS ions activity incorporates multiple science practices, it can take two or even three class periods to fully implement. However, this time investment is critical—it allows students to deeply engage with the material, develop confidence in their understanding, and move beyond rote memorization to meaningful application. Rather than rushing through concepts, students have the opportunity to build connections, test ideas, and refine their reasoning in a way that reinforces both content knowledge and critical thinking skills.
To further support student learning, this lesson includes a digital notebook powered by BookWidgets that allows students to work through each component at their own pace. The built-in immediate feedback ensures that students can self-correct and refine their understanding in real time, reinforcing the student-centered, inquiry-driven approach that makes this lesson so impactful.
Want More Engaging, NGSS-Aligned Chemistry Lessons Like This Ions Activity?
This NGSS ions activity is just a glimpse into what every lesson in my micro2MACRO curriculum delivers—engaging, student-centered, and inquiry-driven science instruction that goes beyond memorization and into deep understanding.
With micro2MACRO , you’ll have a fully-structured, year-long chemistry curriculum designed to help students think like scientists, discover patterns, and apply their knowledge with confidence. Every lesson follows the same proven framework—integrating models, inquiry, and even challenging science and engineering practices like using mathematics and computational thinking—to make even the most challenging concepts accessible and engaging.
Not a Chemistry Teacher? Apply These Inquiry-Based Strategies to Any Science Content!
If you love the student-centered, NGSS-aligned approach of this ions activity but teach a different science subject, the Digital Instructional Design Studio is for you!
Inside, you’ll get the tools, strategies, and support to design engaging, inquiry-based lessons for any secondary science course.
Whether you teach biology, physics, earth science, or general science, this student-centered science system helps you create and deliver lessons that get students thinking, questioning, and discovering—no matter the core ideas of the content.
