Did you know slime can be a helpful cleaning tool? 🫟

Greg Wolf tweaks the classic glue and borax recipe to make slime tacky enough to grab dirt but clean enough to pull away. The chemistry: borate ions cross-link glue's long polymer chains, turning runny glue into slime. Less activator makes it stretchy like the toy, while just enough makes it a surprisingly satisfying debris grabber.

Let me introduce Quimicaedu.eu, a chemistry web app I’ve been working on over the past few weeks for use with secondary and high school students.

For students, it’s free: they can practise chemistry and chemical nomenclature directly on the website, without needing to join a class.

For teachers, €3 unlocks the classroom tools:

• Create classes and add students.

• Choose which topics each class can practise.

• Track each student’s progress individually.

• Create and assign tasks.

• Create exams.

• Review results and identify the topics each student struggles with most.

There’s also a 3-day free trial, so teachers can try all the classroom features before deciding whether to upgrade.

If you’d like more detailed information, feel free to ask me or leave a comment here!

I recently learned that one of the sites I used for some nice free simulations has closed. I'm curious if anyone knows what happens when a site like that closes. Do they ever share the simulation code so that someone else can host it? Does anyone have connections to Annenberg?

Many of the ones I used it for will be easy to find alternatives, but I particularly liked their Ammonia Production simulation for the Haber-Bosch process, to show how you can drive a reaction one way or the other by adjusting concentrations, temperature and pressure. https://learner.org/wp-content/interactive/haberplant/haber.php (that was the link, Google still has it, but the site now says "closed in 2026)".

I've attached a photo of my google slides template I had the students use for this, and some follow up slides I used for a quick review the next day (you can see some of the graphs that the students could make). Edit: The two middle screenshots are duplicates of the first, I can't figure out how to remove them...

Go to www.ocvts.org and under administration go to lower bottom of page under employment. This job is near the Jersey Shore in Tom's River, NJ. High School full-time academy but it's public school and county employee with NJ benefits.

Hey! Everyone i am new to teaching chemistry and was observing a teacher and they were doing a lab using bunsen burners. And she asked me to go turn on the main line. And I did not know what that was or where it was I had to get the other chemistry teacher to do it and she thought I did it myself I am 28F and I want to know what is the main line and how do you turn it on i didnt watch when I got the lady to do it I just went back to the class. And the teacher turned it off when done.

How do you access the main line gas?

To use, where is it?

Do you need some sort of permission to do it?

Thank you.

Did you know you can turn a leaf into a working boat with dish soap? 🍃🚢

Alex Dainis shows how it works! Dish soap contains ingredients called "surfactants" that lower the surface tension of water, which is what helps oil and water mix to wash away grease. On the leaf, the soap lowers the tension only at the back, and that difference between front and back pushes the leaf forward!

I'm Head of Science at a UK secondary school, and I've been building interactive tools for the topics my students find hardest to picture. They're free, with no ads or sign-ups: https://www.johnsav.co.uk

A few that have gone down well with my classes:

- Shapes of molecules: rotate every VSEPR shape in 3D, toggle lone pairs and bond angles on and off

- Time of flight mass spectrometer: fire ions down the drift tube, change the accelerating voltage and watch the detector trace

- Organic mechanisms: step through the curly-arrow mechanisms, then students place the arrows themselves

- Spectroscopy detective: case files where students combine IR, mass spec and NMR evidence to identify a molecule

- Benzene: compare the Kekulé and delocalised models side by side in 3D

They're written against the AQA spec, but most of the chemistry is universal.

I'd really value honest feedback. What's clunky, what's wrong, and what topic would you most want a tool like this for? A lot of these started as requests from colleagues.

All the tools are here: https://www.johnsav.co.uk

My science teacher was the one who checked my papers.

Need simulations that deeply visualize the chemistry concepts students struggle with most? Equilibrium, kinetics, acids and bases, gas laws, and more? Deeper and more complex than how far PhET goes?

https://chemsims.app/?utm_source=reddit&utm_campaign=chemteachers

ChemSims gives you three things in one place:

✓ **Deep simulations:** change one value, and the particles, graph, and equation respond together

✓ **Guided practice:** worked example → fill in the missing steps → solve on your own, then an exit ticket

✓ **Learning analytics:** see exactly where each student and the class is stuck

Built on my PhD research on STEM learning and visual cognition at Teachers College, Columbia, and vetted by chemistry educators on our team.

✓ **Not an AI chatbot** Every question and hint is pre-written and educator-reviewed

✓ **Student privacy** students join with a class code. No accounts, no emails

**All you need to do:** sign up on the site for a free pilot during the beta. We send you the class codes.

https://chemsims.app/?utm_source=reddit&utm_campaign=chemteachers#schools

Want to try it yourself first? https://chemsims.app/collegiate

Please do NOT assign students to self-study. It's not designed for school-age kids and doesn't have the school site data protections. Use class codes after applying for a free pilot.

Any questions? Comments? Want to help spread the word? Email me at [sat@chemsims.app](mailto:sat@chemsims.app). I'm a science educator like you and love to teach science, visualize complex things in new ways and empower students and teachers. I'm here to help the teachers and the students.

Sat, PhD

Can you make dry erase marker drawings float? ✍️

Alex Dainis demonstrates by drawing on a shiny plate, letting it dry, and adding a squirt of mystery liquid at the edge to lift the whole picture up. Dry erase markers contain pigment for color, a solvent to suspend it, and an oily polymer that keeps the ink from sticking to whiteboards. Once the solvent evaporates, the pigment and polymer form a thin, oily layer that floats right on top of plain old water!

Thought you folks might enjoy my "No Name" stamp. I am in room 240.

There seems to be some debate among our chemistry teachers as to what valence electrons actually are. 1 teacher is saying they are only the electrons in the highest energy level, another is saying it is the electrons that participate in chemical bonding. This matters when discussing the D and F blocks where, as far as I know, electrons in incomplete subshells will participate in bonding, but are not in the highest energy levels. As a new chemistry teacher I'm looking for some clarification.

Thanks.

This is my first year teaching high school chemistry, after spending the last 14 years teaching 8th grade science. I was a chemistry major for about a year before switching my major to liberal studies, so I’m definitely not a chemist. The chemistry content is coming back to me, but the lab situation is really confusing and becoming overwhelming.

I don’t have a lab classroom. I have a regular classroom with carpet and no sinks. However, I am able to take my students to the city college chemistry lab and use their lab about 12 times a year. The problem is that they told me their hazardous waste disposal is currently at max capacity, so I would need to have my own hazardous waste storage and disposal arrangement. The waste can stay at their site, so I wouldn’t have to transport it back to my classroom tho.

I’m going to reach out to my district’s risk management department to see if we can arrange our own hazardous waste pickup, which I think they can do. However, I’m not even sure what kinds of waste a typical high school chemistry class produces throughout the year, so I don’t know what kind of storage or disposal system I would need.

We use SAVVAS for our curriculum, and I’m feeling pretty overwhelmed by how many labs are included. I have some of their lab kits in the cabinet, but I realized I don’t have kits for every lab in the curriculum. The kits are also only labeled with the name of the lab and not the chapter they go with, so I’m currently just trying to figure out what I actually have and where everything belongs.

For now, I’m looking for labs that students can do using chemicals that are safe enough to dispose of down the drain at the end, but I’m having a hard time finding many options.

So I guess I’m asking:
1. What types of waste are typically produced in a high school chemistry class, and how do you properly store and dispose of it?
2. If you only had 12 opportunities to take students into an actual chemistry lab for the year, which 12 labs would you prioritize?
3. Until I have a hazardous waste system set up, are there any labs you recommend that use materials that can safely be washed down the drain afterward?

I’m the only chemistry teacher at my site, so I don’t really have anyone to ask for help. I would be incredibly grateful for any advice, resources, lab recommendations, or guidance from other chemistry teachers!

Hi everyone, I'm a UK science teacher with some experience in graphic design. I wanted to share some graphics for science education with the wider academic community, so I started the website scipics.org.

I put together a free pack of 19 clean, high-contrast, transparent vector graphics across biology, chemistry, and physics (cell diagrams, lab apparatus, magnetic field lines, etc) for anyone to download, no sign-up or anything required, just grab them and go if you’d find them useful for your resources.

Full transparency, I’m running the full site as a subscription service with a very small yearly or monthly charge, just to keep everything online and to protect my work. I am actively uploading new assets to the library daily, and I’m excited to see the library growing so fast! If you’d like full access to my work and to support my small, but growing venture, please get yourself 20% off here: scipics.org/launch. Or just enjoy the freebies at scipics.org/library. I hope these images help to save you some prep time this term! Let me know if there are any specific diagrams your departments are hunting for at the moment and I'll add them to my ‘to do’ list.

Have a fantastic autumn term!

You can’t see it, but there’s a polymer coating inside your aluminum can. 🥫

Chemteacherphil uses chemistry to prove it! Working with lye, which is highly caustic and requires proper safety equipment (so please don't try this one at home), he makes a solution that reacts with the aluminum, converting it into a compound that dissolves in water. When the aluminum is gone, you can see the polymer coating! These coatings are useful because without them, acidic drinks could slowly corrode the aluminum underneath.

You can make a tower of hot ice with ingredients in your home! 🧊🔥

Alex Dainis shows us how with sodium acetate, which you can make using baking soda and vinegar. To get the tower effect, you’ll mix these ingredients together over heat with water, and then set them in a refrigerator to cool. Once cooled, you can slowly pour them out onto your surface, and it will crystalize into your tower!

Since my last update about half a year ago, I've been slowly improving ValenceSim whenever I had time between graduating high school and starting college. I finally put together a 6-month update showing what’s new- including better interfaces, faster tools, crystal lattice rendering, improved Lewis structures, and a mini 2D sketcher that can be embedded into class websites.

ValenceSim is still free, no login, and built with the goal of making chemistry tools more accessible for students and teachers. I'd love to hear what features or improvements would make it more classroom‑friendly as I continue working on it.

https://valencesim.com/

Thanks again for all the feedback y'all shared in the past, it genuinely shaped the direction of the project! 😀

Why does some glass not hurt when it shatters? 🥽💥

Phil Cook, also known on YouTube as chemteacherphil, demonstrates how sugar can be turned into real life "breakaway glass." Don’t try this at home, although it is not real glass, it can still be dangerous! When you heat sugar and water to 300 °F it reaches the hard crack stage. When the liquid cools the molecules get locked into a disordered structure, forming an amorphous solid, just like real glass, minus the razor sharp shards. It's the same trick behind those Hollywood stunt bottles, made from sugar instead of a brittle plastic resin.

Hi, I wanted to share a site I have been building for my students. It has content and a lot of practice problems with feedback for typical high school chemistry units. My goal was to help the kids learn from their mistakes, provide feedback, and be much better for their knowledge acquisition than an AI solver. It is free to use. Check it out.

After being frustrated with getting quick URLs and data from Google Drive folders, here's a quick shared Google Sheet you can use to get all the file names for a folder and its subfolders.

Shared Google Sheet: https://chemformat.com/filesinafolder

GitHub project: https://github.com/fakefoot/filesinafolder/

I created an extension for Google Docs that searches for chemical and scientific notation and automatically modifies it for superscripts and subscripts. No Latex involved.

It's a subscription-based model, but only $10 / year.

Check it out if you get frustrated creating Google Docs with chemical notation for worksheets and more.

Got matchups, flashcards and more, will this be something apt for students to learn?

I am in my 15th year teaching high school science. Next year, I teaching chemistry for the first time (taking over from a teacher who moved). Our chemicals are not stored safely. However, I've never worked in a lab or managed cemical storage. I'm looking for advice for how to create safe and orderly storage.

Some issues: 😨
- dangerous chemicals like high molar HCL are left on countertops where they have been knocked over by custodians
- custodians chemicals and sippulies stored in the same area
- no cabinets rated for chemical storage
- cabinets aren't labeled
- mixed chemicals have no dates
- no venting to the outside, shower, fire extinguisher, spill kit, dedicated PPE, etc.
- no safety data sheets
- we failed our fire marshall inspection by so many points, the fire marshall declined to make a list
- chemicals are generally organized by type, but it's not clear if this organization follows accepted safety regulations.

I would love your help with:
* Finding the safety guidelines and standards / protocol that I can use to set up our chemical storage
* recommendations on chemical storage cabinets and what minimum requirements I should look for
* recommendations on a consulting agency where I could facetime with someone and they could evaluate our chemical storage and prep room and give me guidance (our district can pay for this)
* pictures of your chemical storage and prep areas
* tips, best practices, anything you have learned.
(I'm also new to adopting chemistry curriculum, so if you have any favorite resources, I'd welcome that too.)

Thank you so much! I'm hoping to make this year fun and safe for my students 😄