Happy New Year from!

Hello everyone, and Happy New Year! I hope that you and yours have been able to stay safe and healthy during the pandemic. Now that 1st Semester is ending for many of us, I wanted to let you know about the improvements to over the past few months.

Faster web hosting

First, and most importantly, I upgraded the hosting package for the website! The site should run much faster now, especially when lots of people are using it at once, so I’m hoping this improvement is noticeable and makes the site a little more user friendly.‘s popularity has increased a lot, and the site has frequently had over 15,000 hits and 2,000 unique visitors each weekday since mid-September, which is WAY more than last school year. (Interestingly, the peak was on December 14th, 2021, when there were 2,984 unique visitors and 25,937 hits, so I’m guessing that was due to students preparing for 1st Semester Exams.) The site reached two million total hits to date in November 2021, the vast majority of which came since this past August, so it was definitely time for an upgrade! Thanks to everyone who purchased site licenses this school year so that I could pay for the upgrade. (Please note: as a result of the upgrade, email notifications for assignments are currently not working, but I should have them working soon.)

Three new quizzes

Next, there are three new quizzes since my last newsletter in August:

I hope you find them to be useful for your students. Those three quizzes were all requested by multiple teachers, so thank you to everyone who has contacted me with suggestions, because they really help me prioritize what to work on next. I have more new quizzes planned, so hopefully I’ll be able to find the time over the next few months to work on them.

New quiz features

Two notable quiz improvements: you can now generate empirical formula problems in the Mass Ratios & Percent Composition Quiz, so now it’s called the Mass Ratios, Percent Composition & Empirical Formulas Quiz. Also, I modified the Significant Figures Quiz so that it sometimes randomly adds a few extra zeroes past the decimal point, and you can include random units in problems to make them a little more realistic.

New Dashboard features

I added several new features to the Dashboard, including the following:

  • Make copies of existing assignments
  • Export quiz results by class
  • Export the highest quiz score for each student on a particular assignment
  • Other visual and efficiency improvements

I also recorded several instructional videos for the Dashboard, and I added an “md5 hash” to check if students were using the back button to check and fix their answers on quiz assignments (so you may have heard from one of your students if they tried doing that recently!).

Lots of bug fixes

Of course, there wouldn’t be a update without bug fixes – there currently are 46,000 lines of custom code for the quizzes and other scripts that run the site! – so here’s a list of what I was able to squish with your help:

  • existing student accounts were getting corrupted when they tried to join another class; the registration form now checks to make sure an existing student is logged in before allowing them to join a class by using a join code
  • the registration form was grabbing the wrong user ID when creating a new account with a join code
  • several Dashboard specific bugs:
    • archived classes were showing up on assignment form
    • some assignment settings were wiped out immediately after the assignment was created
    • the “Show individual students” link wasn’t working on the Create Assignment form
    • student names were shown as “First Last” in Quiz Results; “Last, First” made more sense
    • assigning quizzes to “All of your classes” didn’t work properly; I changed the way assignments are linked to classes and students in the database
  • Quiz specific bugs:

+ lots of under-the-hood improvements!

If you come across any other bugs, please let me know and I’ll do my best to fix them!

Equity and opportunity

This school year has been much more difficult than many of us anticipated, including me, so I wanted to celebrate the fact that there are currently 45 high-poverty public schools signed up for, which means 54 teachers and their 762 students are able to access the Dashboard LMS at no cost to themselves or their schools. If you purchased a site license, you’ve helped me pay for the web hosting, SSL certificate, domain registration and other business costs that allow me to give free site licenses to schools that have the fewest resources. There’s a lot of student talent out there in all kinds of places, so I’m hoping that will help more students do well in Chemistry and realize their full potential. Thanks for helping make this possible!

Discounts, for a limited time!

In the spirit of making the Dashboard available to more chemistry students, for those of you who haven’t yet purchased a site license for this school year, I’m now offering a discounted rate of just US$30 through July 1st, 2022! With a site license, you’ll be able to create accounts for all of your students and create as many quiz assignments as you’d like, which lets you track your students’ progress as they master different chemistry skills in line with your own curriculum. More info about the Dashboard is available here.

For existing customers, as a show of my sincere gratitude for your support so far, you can renew your license for next school year now through April 1st for only US$40, which is a 20% discount from the normal rate! This will help me secure the upgraded web hosting for next school year so that the site remains fast and accessible for as many people as possible.

One last thing – if you have a site license, make sure you have your school listed on the “About” page by going to the Dashboard, clicking on “Your Info”, and then checking the box next to “Display School on” and clicking the pink “Update your info” button. (Please note that this is completely optional but it does help support the site for free.)


Thanks again for all of your feedback, suggestions and support! When I started in the summer of 2020, I never could have imagined that it would have grown to have so many teachers and students using it every day. Working on the site has been a true source of joy for me during such a difficult time. As always, take care, stay safe, and keep in touch!



New quizzes and features to start the new school year

Hello there! I hope you’ve been able to take the summer to relax and recharge for this upcoming school year.

First, I’d like to thank you for your support over the past school year. went from being an idea I was tossing around with a few of my colleagues during the 2020 lockdown to an educational website that has added over 1,000 users and has had over 900,000 hits! I’ve truly been humbled by the positive feedback and constructive criticism I’ve received during that time. Numerous teachers (you know who you are!) requested new quizzes, suggested new features and pointed out lots of bugs that helped me improve the site and allow me to focus on doing something positive instead of worrying about covid-19 and what school would look like in the fall.

Several of you have already signed up for site licenses, which is awesome! If you had a free account last year but your school isn’t “economically disadvantaged” (I hate that term, btw) with at least 50% of your students on free/reduced lunch, please consider purchasing a site license this school year for only $50. Website hosting isn’t free, so my first goal by selling site licenses is to break even, and then I’m planning to upgrade the hosting so that runs much faster and can support thousands more Chemistry students and their teachers. I can accept payment through Venmo, Zelle, school purchase order or personal check, so please contact me at if you’re interested in purchasing a site license!

On to the exciting news – LOTS of new features! I’ve been working over the summer to try to squash as many bugs and add as many new features as possible. My focus was on trying to make easier to use while also increasing its usefulness to Chemistry teachers and students, so I hope I’ve accomplished those goals. Here’s what’s new:

New Quizzes!

  • NEW Scientific Notation Quiz
    • convert between scientific notation and decimal notation, includes multiple choice questions
  • NEW Chemical Equilibrium Quiz
    • write chemical equilibrium expressions, convert between Kc and Kp, and calculate equilibrium constants and chemical quantities

Improvements to the Dashboard:

  • teachers can now assign a quiz to multiple classes or students
  • teachers can delete multiple student accounts or generate new passwords for multiple students accounts
  • teachers can archive multiple quiz results once they’ve been reviewed
  • quiz results from 2020-2021 school year have automatically been archived
  • added a giant “join link” popup for teachers to show on the screen for easier student enrollment
  • Dashboard automatically generates a QR code for each assignment
  • cleaned up the overall appearance and improved the interface of the Dashboard
  • custom assignment names now show up in CSV result exports

Additions to documentation:

Improvements to all quizzes:

  • new Presentation mode! (I’m really excited about this!) One question per screen with larger font and immediate correct answer (site license required) – try it out on the Significant Figures Quiz!
  • simpler given values for most quizzes to make math problems easier
  • better scientification notation handling so students can enter a number like “6.02 x 10^23” instead of “6.02E23”
  • fixed formatting on quizzes and results so that they look similar
    improved formatting of “printable” quizzes
  • added cute “Generating Quiz” and “Scoring Quiz” animations!
  • add placeholder text to some input boxes to make wanted values a little more obvious
  • updated the example quizzes on the Sample Chemistry Curriculum page to include new features
  • LOTS of other under-the-hood improvements!

Quiz-specific improvements:

I’m also working on several new features and quizzes that I hope to finish soon:

  • new Lewis dot structures quiz
  • new photon wavelength & frequency quiz
  • new reaction rates quiz
  • better integration of Dashboard features so that they’re faster and easier to use
  • prevent students from resubmitting answers for the same quiz instead of retaking the quiz with new problems
  • more quizzes with multiple choice questions
  • better quiz result filtering in the Dashboard
  • and more!

If you have any suggestions for new quizzes or features, please feel free to drop me a line at any time at or by filling out the Contact form. Also, please spread the word about the site:

Thanks again for all of your support this past school year, and I look forward to doing what I can to make this upcoming school year a little easier for you and your students. Take care and stay safe!


The new year brings three new quizzes and lots of new features

Happy New Year, everyone! I hope you’re all doing well, staying safe, and managing your sanity during this challenging school year. After having some time to work on over Winter Break, I wanted to send you an update to let you know about three new quizzes and a bunch of new features that I hope will make your lives a little easier.

First, the three new quizzes in alphabetical order:

  • Molar Conversions Quiz
    • convert between moles and a variety of units
    • chemical formulas or compound names; simple or word problems
  • Isotope Naming & Notation Quiz
    • name isotopes, determine isotope notation and count number of subatomic particles for hundreds of isotopes
  • Thermochemical Equations Quiz
    • over 100 thermochemical equations with heats of reactions
    • stoichiometry and limiting reagents problems
    • balanced and unbalanced equations; chemical formulas or names; grams and moles; percent yield
    • creating this quiz also added 192 new balanced chemical equations that are used by other quizzes for more variety!

I also added a new score correction feature to the Dashboard that allows you to override quiz items that has erroneously marked as incorrect. Just view the quiz result details, check the box(es) next to the items you’d like to mark as correct, and click the “Save Update” button at the bottom of the page. You can also leave feedback (comments) on quiz results that can be viewed by your students just like in other learning management systems. Another new Dashboard feature is the ability to archive old quiz results so they don’t show up in the list any more unless you want them to be displayed. This has no impact on whether or not a student can see their quiz results, because students can’t currently archive their results. Finally, by request, teachers now have the ability to filter their quiz results by class.

In addition to these new features and quizzes, I made two quick bug fixes, one giving teachers the ability to disable assignment email notifications to students (this option wasn’t displaying correctly before), and some beta decays in the Nuclear Reactions Quiz were generating way too many products, resulting in questions that violated the law of conservation of matter. Oops! There were also some little bug fixes thanks to teacher and student feedback that were mostly focused on simple mistakes, like a student putting an extra space before or after an answer that resulted in an item being marked incorrect when it shouldn’t have been.

The last new feature that I’ve added – reference sheets! For decades I’ve given my students various handouts of equations, ions, etc., as have many of you, but a teacher contacted me asking for a list of the polyatomic ions used the Naming Chemical Compounds Quiz, so I uploaded my reference sheets to Google Drive, updated and tweaked them, and I’ve made them available to you to use with your students. You can make copies in Google Docs or download them as Word documents and modify them however you like, or you can just download them as PDFs and print them for use in your own classroom (if you’re currently teaching in person, like I am). There are reference sheets for ions, common chemical equations, and SI prefixes, but if I’ve left out an important topic, ion, or equation, please let me now!

Finally, check out these cool website visitor stats:

Today (January 5th, 2021) represents the day with the greatest number of hits and unique visitors since began this past summer! You can also clearly see where Thanksgiving and especially Winter Break happened, which was great timing because I used that time to run all kinds of backend site maintenance. The most popular quiz to date? Naming Chemical Compounds, of course – the first one I wrote for my school blog so many years ago, which has had over 48,000 hits since August 1st.

I can’t thank you enough for all of your help finding and reporting bugs so I can fix them while also requesting features and suggesting new quizzes so that I can make the site better. If you’re new to, here are some quick and easy things you can also do to help make the site more popular:

I hope you’re all staying safe and healthy! We went back to face-to-face “hybrid” teaching today after temporarily going fully remote in early December, so with covid cases back on the rise due to the holidays, I’ve started wearing a KN95 mask under my cloth mask, and it was surprisingly comfortable compared to breathing through the PM2.5 carbon filters I inserted into my cloth masks for the first four months. They’re just so expensive – US$2 each in a 20 pack! – so if you have any hot tips for cheaper KN95’s, I’m all ears. Please feel free to drop me a line at any time at or by using the Contact form. Take care!


Bugs are great in ecosystems, but not on

Hello again!  I hope you’re all doing well and staying safe.  I know that most if not all of you have started back to school, whether it’s remote learning, “hybrid” or face-to-face, so I’m sure this has been a stressful time for all of us as we re-learn science teaching during the pandemic.

At my school, we just finished our third week of hybrid or “blended” learning, and the experience so far has been… interesting.  Because I see some students on Tuesday/Thursday, some on Wednesday/Friday, and some that are remote only, I have ten seating charts and fifteen rosters for five classes, so just keeping track of who’s supposed to be in which class on what day has been an adjustment.  Add in students who are sick and more who are quarantined (like our entire football team for 10 days!), and I’m just hoping that my students learn anything this school year without going crazy.  For those of you going back to face-to-face teaching soon, my main recommendation is that you should expect everything you do to take at least three times as long as it normally does, so do less, if possible.

Because of that, I haven’t been able to do much with, except when I finally got caught up with my schoolwork this week, which was just in time for a MAJOR bug involving assignment email notifications!  A few of you wrote me and said your students were getting inundated with dozens and dozens of notifications, sometimes for assignments they’d already completed and sometimes for assignments that weren’t meant for them.  I’m terribly sorry that happened – I know that my kids (both my biological children and my students) are getting slammed right now with email notifications from Google Classroom, Remind, FlipGrid, you name it – so I’ve fixed that bug, along with another one that created duplicate accounts when students used a Registration code.  It turns out that spelling is important, not only in real life, but in programming as well! ??‍♂️

Thanks to your feedback, I’ve also fixed a number of other bugs:

  • students could not retake quizzes even when the assignment was set to allow them to retake
  • teachers couldn’t update student passwords
  • student names were not sorting properly in the Dashboard > Users page due to capitalization issues
  • any student answer with neptunium in the Nuclear Reactions Quiz was marked as wrong, even it was correct (that was a weird one!)

I’ve also been told that some students are not receiving registration emails, either because their district blocks it or the email went to their Spam folder, so I wanted to let everyone know that I wrote lots of documentation for the website, including how to reset a student password.  However, you’re welcome to have students contact me, either by filling out the Contact form or by emailing me directly at, and I will gladly take care of their password issues for you.

There’s good news besides bug fixes.  Several of you have asked me to be able to filter and sort your Quiz Results and your Users list, so I was able to add those features today.  You can sort some columns by clicking on the header of that table, and you can filter results by class, student or assignment by using the dropdown menus.  I hope this helps you keep track of your students’ progress a little more easily!  The sorting feature involves JavaScript, which I’m really not good with, so if you’re having any issues with it, let me know.

If you feel is useful for your students, please continue to tell other teachers about the site!  If you’re on Twitter, please consider following me at @ChemQuizDotNet.  I haven’t had the time to tweet much lately, but I hope to share tips and tricks for using the site in the near future.

One last fun fact: the most popular quiz on the site this past week was the Significant Figures Quiz, with over 5,000 visits!

Sig Figs are popular on but not in Chemistry class

This makes sense since sig figs are such an important fundamental concept in Chemistry (that every Chemistry student hates until they take a college lab course and finally understand why some numbers matters and others don’t).

Thanks again for all of your patience and support as I iron out the bugs and try to make easier to use for teachers and their students.  I appreciate all of the feedback I’ve received so far, so please feel free to email me at if you’re having any issues or if you have an idea for a new feature or quiz.  Good luck this upcoming week, and stay safe!


Welcome to new schools, three new quizzes, some bug fixes, and a small favor

Hello fellow Chemistry teachers!  I hope you’re all doing well, staying safe, and making time for your own mental health as we all prepare for the most uncertain school year in modern times.  Like many of you, I’ve been tasked with figuring out how to teach my science classes to some kids on Tuesday/Thursdays and other kids on Wednesday/Fridays while also teaching kids who are connecting from home, including my own child.  It’s a huge mess, so I hope that the practice quizzes on will play a role in helping you meet the needs of your students.

First, I’d like to welcome the new schools that have signed up to use this upcoming school year!  We’re up to 31 schools and a private tutor, which span across 16 states and 2 provinces of Canada, which is so cool!  I’ve reached out to just about every school district in Ohio that I know is starting with remote learning (I’m keeping a list out of curiosity), but it’s impossible for me to track what’s going on in every state, so please feel free to spread the word.  Any school district with a student population that’s greater than 50% “economically disadvantaged” will receive a free site license to the Dashboard, regardless of their pandemic plans, because I want to try to help as many underprivileged kids as possible during this huge mess in our country.

Now, on to the big news: there are three new quizzes available on!

I also added some simple organic compounds to the Mass Ratios & Percent Composition Quiz just for fun. 🙂  I’ve thought about writing a quiz for naming organic compounds, but that gets so complicated so quickly that it makes my head hurt just considering it!  I can’t imagine how difficult it would be to teach any organic remotely this year.

A few of you have made great suggestions to me for new quizzes to write, and I’ve added them to the list.  I’m an amateur programmer during my best moments, so I have to think about things for a while before they click in my head.  I’m going to try my best to get to your requests soon!

Also, I’ve also fixed a few bugs thanks to several of you reaching out to me about issues you were having, including a real stinker involving student quiz results.  I can’t thank you enough for pointing out when things don’t work properly!  Please keep the bug reports coming.

Finally, I’d like to start listing schools who are using publicly on the website, but I won’t list your school without your permission.  If you’re okay with having your school listed, please take a moment to check the opt-in box in your User Info in the Dashboard and click “Update your info”.  Totally optional!  Once a few schools have opted in, I’ll list them on the About page.  Your school name won’t ever be used for anything else besides that list on that one page.

Please don’t hesitate to reach out to me if you have any problems using the site or suggestions for new quizzes or improvements.  You can always contact me at or by filling out the Contact form.  Thanks again for being a part of this grand experiment, and good luck this school year!



Three (almost four!) new quizzes, new features in others

Hello again!  I hope you’re all doing well.  As this uncertain summer draws to a close, I’ve added three more quizzes to that are available to everyone now:

I’m also really close to finishing a new Acid-Base Neutralization Quiz, so you can get a preview of that while I work out the bugs and add options.

I also added new features to two existing quizzes:

I’m planning on adding two or three new quizzes this upcoming week, but if you come across any bugs or think of any new features you’d like to see, please let me know by emailing me at or by filling out the Contact form.  I hope you’re all staying safe and getting some rest before the school year starts!



Welcome to the newsletter!

Hello again, and thanks for signing up for the newsletter!  I really appreciate your support as I start up my website of chemistry practice quizzes.  I plan on sending this newsletter out once a week, and it’s intended to be informative, so for any reason if you don’t want to receive it, just send me a quick reply with “Unsubscribe” and you won’t get it again.  Also, I have a particular distaste for marketing emails, so I won’t share your email address with anyone for any reason.

A lot has happened in the last month, and like many of you, I’m not sure what our school district is planning to do this Fall.  To keep my mind off of it, I’ve been writing new chemistry practice quizzes!  Since mid-June, I’ve added the following quizzes:

Plus, I’ve added some new features to existing quizzes by request:

I’ve also cleaned up the quizzes so that they largely look the same and have similar features, like being able to generate a printable worksheet in each quiz.  If you have any suggestions for improving existing quizzes or making new ones, I’d love to hear them!

There have been some changes to the Dashboard to make it easier for you to assign quizzes to your students.  One feature is the ability for your students to join with a simple registration code.  You can also have them join a specific class directly.  Each school and class has its own six-character registration code, which you can see in the Dashboard under the School Info and Classes pages, respectively.  Simply have students go to, fill out the form, and enter the registration code.  This should create their account and add them to your school or class depending on what code they entered.

Another feature that I think will be particularly helpful is the shortlink.  When you create an assignment, notifies students through email, but we all know that teenagers never check their email accounts (my own kid included!).  In the Dashboard’s Assignments page, you’ll see a table listing all of the assignments you’ve created.  Below each quiz name is the shortlink to the quiz, like this:


You can send this shortlink out via whatever student messaging system or LMS you use (Remind, Google Classroom, text, etc.).  When the student loads the shortlink, if they’re still logged in to, it will give them the option of completing your assignment without having to go the Dashboard first, so this should make it easier to disseminate your quiz assignments.

Additionally, I’ve created lots of Documentation pages with steps on how to do everything on  I’ve also created a Sample Curriculum page with over 50 preconfigured quiz assignments that teachers can copy, modify and use simply by clicking a button!

Finally, I just wanted to thank you again for giving a try!  It’s my attempt to help other science teachers out in what is going to be a memorably difficult school year for all of us.  I’m sure there will be bugs on the site, so I appreciate your bug reports and patience as I track them down and stamp them out while also teaching my own classes (whatever that ends up looking like!).  Take care, keep in touch and stay safe!