Rate of Dissolution Lesson Plan (TEKS 7.6E): A Complete 5E Lesson for Temperature, Surface Area, and Agitation

Inside the Rate of Dissolution 5E Lesson

The 5E instructional model walks students through five phases: Engage, Explore, Explain, Elaborate, and Evaluate. It flips the traditional lecture-first sequence on its head. Students explore a concept hands-on before you ever explain it, which means by the time you do explain it, they have something to hook the vocabulary onto.

I switched to the 5E model years ago and stopped going back. Kids retain more, ask better questions, and stop staring at me waiting to be told the answer. The Rate of Dissolution 5E Lesson is built on this framework from start to finish. Here's how it plays out across the five phases.

🎯 Engage

Day one is a teacher-led "who can dissolve a sugar cube fastest" challenge. Each small group gets the same sugar cube and the same volume of room-temperature water, plus a few simple tools (a spoon, a cup of hot water from a thermos, a cup of ice water, a small mallet or the back of a spoon to crush the cube). They follow the step-by-step student sheet to plan their attempts, run their tests, and record what worked.

By the end of the period, kids have a sketch of every attempt on their student sheet, drawn in their own hand, and they can explain in their own words which conditions made the sugar disappear fastest. Nobody has heard a vocabulary lecture yet. That's the point. They're walking into the rest of the unit with a working mental model, not a memorized list of three factors.

What's included in the Engage:

• Teacher directions for the sugar-cube challenge
• Printable student observation sheet
• Answer key for the discussion questions
• Four learning objective slides (standard verbatim, "Investigate" verb highlighted, "I CAN...", and "WE WILL...")
• An illustrated Chemistry Word Wall in English and Spanish covering the full unit vocabulary

🔬 Explore

The Rate of Dissolution Station Lab is the heart of the Explore phase. Students rotate through 8 stations (plus a 9th challenge station for early finishers) over one class period. The Station Lab is split into four input stations (where kids take in new information) and four output stations (where they show what they learned).

The four input stations:

• 🎬 Watch It! — Students watch a short video on the three factors that change rate of dissolution and answer guided questions.
• 📖 Read It! — A one-page reading passage at two differentiated levels, with a Spanish version included.
• 🔬 Explore It! — A side-by-side hands-on test where students compare a whole sugar cube to a crushed cube, hot water to cold water, and a stirred cup to a still cup.
• 💻 Research It! — Reference cards with particle diagrams, definitions of the three factors, and worked-out examples.

The four output stations:

• 📋 Organize It! — A card sort where students place scenarios under the right factor (temperature, surface area, or agitation).
• 🎨 Illustrate It! — Students draw a particle-level diagram showing what happens when surface area or temperature increases.
• ✍️ Write It! — Three open-ended questions in complete sentences (this is where you see who really gets it).
• 📝 Assess It! — A short formative check with multiple choice and a fill-in-the-blank vocabulary paragraph.

Print and digital versions are both included. If you want the full breakdown of what happens at every single station, what students produce, and how to set it up, that's in our dedicated Station Lab post.

→ Read the full Rate of Dissolution Station Lab walkthrough 8 stations, materials list, teacher tips

The Station Lab is included in the full 5E lesson. You don't need to buy it separately if you're getting the whole unit.

📚 Explain

Here's the real payoff of doing the Engage and Explore before the Explain: by the time kids hit this phase, they've already crushed cubes, used warm water, and stirred sugar with their own hands. They have a working understanding before you ever start naming things. The discussions get deeper, the questions get sharper, and you spend less time defining and more time pushing their thinking.

The Rate of Dissolution Presentation walks 7th graders through the full scope of TEKS 7.6E, one concept at a time. The deck opens with a quick reset on aqueous solutions (solute dissolved in a solvent, water as the solvent in this case) and on dissolution itself (a physical change where a solute breaks apart and distributes evenly through the solvent). From there it defines the rate of dissolution as how fast that process happens, and names the three factors that change it: temperature, surface area, and agitation.

Each factor gets its own dedicated section in the deck, and each one is anchored in particle-level reasoning. Temperature is a measure of the average kinetic energy of the particles. Higher temperatures mean faster-moving particles. Faster particles bump into the solid more often and harder, breaking pieces away from the surface more quickly. That's why sugar dissolves faster in hot tea than in iced tea. Surface area is the second factor. The deck uses a clean side-by-side: two objects that have the same volume but very different surface areas. Then it applies that idea to a sugar cube versus crushed granulated sugar. Same amount of sugar, but the crushed version has way more surface exposed to water at once, so more particles can dissolve at the same time.

Agitation is the third factor. Stirring, shaking, or beating the solution moves the solvent particles around faster. That brings fresh water into contact with the solid surface and carries dissolved particles away so new ones can take their place. A dishwasher example and a washing machine agitator example help students see this in real appliances they use at home. The deck circles back to one critical idea: all three factors change how fast the solute dissolves, not how much can dissolve. Every solution has a saturation point. Past that point, no amount of stirring or heating will dissolve any more solute.

What makes the Rate of Dissolution Presentation different from a typical chemistry slideshow is that kids are doing something on almost every slide. It's not a lecture deck. It's a participation deck. "Your answer:" prompts appear on most slides, Brain Breaks reset attention every few slides (including a side-by-side hot water versus cold water mini-test built right into the deck), and Quick Action INB tasks (a temperature-rate diagram, a surface-area model of a sugar cube, an agitation drag-and-drop) show up throughout. Think About It prompts push deeper into bigger ideas like Jen's bath bomb experiment and choosing the right washing machine for the job. The deck closes with a Check for Understanding tied back to the Essential Question: How do temperature, surface area, and agitation affect the rate of dissolution of solid solutes in aqueous solutions?

The Explain materials in this product include:

• An editable 24-slide Presentation at two differentiated levels (Dependent and Modified), works in PowerPoint or Google Slides
• A guided fill-in-the-blank student notes handout that mirrors the Presentation, with answer key
• A Paper Interactive Notebook (English and Spanish) students cut, fold, and glue into their notebooks
• A Digital Interactive Notebook at both levels with answer keys, for 1:1 classrooms or Google Classroom

The Explain runs across two class periods. The built-in Think About It prompts are where the real discussion happens, so let those breathe.

🛠️ Elaborate

The Elaborate phase is where students stretch what they learned about rate of dissolution and put it into a project of their choosing. In this 7th grade chemistry lesson, that's a Student Choice Project board with six different project options plus a "design your own" pathway.

Students might design a how-to poster for making the perfect cup of hot chocolate (using all three factors), record a video advice column for a younger student who can't get powdered drink mix to dissolve, build a model that shows surface area at the particle level, or write a comic strip where a sugar cube and a glass of cold water debate which one needs to change. There are options for kids who love to write, kids who love to draw, kids who love to build, and kids who love to perform. Whatever the project, the point is the same: students apply temperature, surface area, and agitation to a real-world artifact instead of a worksheet.

Choice is the whole point. By letting students pick how they show their thinking, you get more authentic work for TEKS 7.6E and you actually get to see what they understand about rate of dissolution.

The rubric (the part teachers actually want)

Every project, no matter which option a student picks, is graded on the same 100-point rubric. Five categories at 20 points each:

• Vocabulary (20 pts) — At least four words from the lesson are used in context.
• Concepts (20 pts) — At least two key concepts from the lesson are referenced.
• Presentation (20 pts) — The project grabs attention and is well-organized.
• Clarity (20 pts) — Easy to understand. Free of typos.
• Accuracy (20 pts) — Drawings and models are accurate. The science is right.

The rubric uses a minus / check / plus shorthand on every row so you can grade a stack of projects quickly without re-reading every criterion.

Two differentiated versions in one file

The standard version is for students ready for independent application of rate of dissolution. The Reinforcement version is for students who need additional vocabulary or concept support. Three of the six options are swapped for projects with a tighter vocabulary tie-in, and "design your own" is replaced with "collaborate with the teacher" so kids aren't pitching cold.

✅ Evaluate

The Evaluate phase wraps the unit with a formal assessment. It's not all bubble-in. Several questions hand students images of two solutions side by side and ask them to circle the one that will dissolve faster and then describe why.

The full assessment has 12 questions across five formats:

• Multiple choice (4 questions) covering temperature, surface area, agitation, and the difference between rate and saturation
• Hotspot / visual (2 questions) where students circle the setup that will dissolve faster and explain which factor caused the change
• Multiselect (2 questions) where students pick all the actions that would speed up dissolution from a list
• Short answer (2 questions) on why crushing a solid speeds up dissolving and why stirring doesn't change the saturation point
• Multipart scenario (2 questions) with a real-world setup (a bath bomb, a sugar packet in iced tea) where students identify which factor would speed it up and justify their reasoning

A modified version is included for students who need additional support. Fewer multiple-choice distractors and sentence-starter scaffolds on the short-answer items.

If you've taught all five phases, this assessment shouldn't surprise anyone. It's a chance for kids to show you they get it.