1. Who we are
DONAT STEM (Donat Sciences and Maths, www.donatstem.co.rw) is an independent education project by BIZIYAREMYE Donat, Senior Physics and STEM Teacher at GS BYUMBA INYANGE, Rwanda. It is prepared with reference to the REB competence-based curriculum but it is not an official publication of REB or NESA and is not endorsed by them. Keep your school’s official REB books as your main reference.
By using this website you accept these terms. If you do not agree, please do not use the site.
2. Using the site
- Quizzes, practice books, simulations, Interactive Labs and lesson-plan drafts are free. You do not need an account.
- The site is made for secondary school students, teachers, parents and guardians. Students under 18 should ask a parent, guardian or teacher before paying for anything.
- Please use the site for learning and teaching only. Do not try to break, overload or copy the site automatically (for example with scraping software).
3. Free and paid resources
Some resources are sold to support the project: worked-solution packs, Lab Packs, teacher papers (tests with marking schemes) and print codes. Before you pay you can read free sample pages, and the price is shown on the page. Paying for a resource gives you a licence to use it (section 5); it does not transfer copyright.
4. How buying works
- You pay with MTN Mobile Money and send a WhatsApp message to 0788 804 242 with the name of the resource. Card payment for buyers outside Rwanda is planned; until then write on WhatsApp and we will suggest a way to pay.
- After we confirm your payment we send you a private download link. A link works for 7 days and can be opened 3 times. A print code works for 30 days and for 2 prints.
- Delivery times, lost links and refunds are explained in the Refund and delivery policy.
5. What your licence allows
- Students and parents: use the files for your own study, on your own devices, and print copies for yourself.
- Teachers: print or project the files for your own classes.
- Schools: to share a file with several teachers or classes, ask for a school licence on WhatsApp.
- You may not share download links, send the files to other people, upload them to other websites or groups, or sell them. Each link is personal.
6. Copyright
All questions, notes, drawings, simulations, labs and documents on this site are original work by BIZIYAREMYE Donat, © 2026, all rights reserved, unless another source is named. Links to other websites (for example PhET simulations) are given for convenience; those sites have their own terms and we are not responsible for them.
7. Accuracy of the content
- We check the content carefully, but mistakes can happen. Please use the Report a mistake button or WhatsApp and we will correct it.
- Simulations and Interactive Labs are models: their data are realistic values prepared for learning, not official measurements. Real experiments can give slightly different numbers.
- Some labs use invented examples (for example the fictional medicine in the medicine lab). Nothing on this site is medical, financial or legal advice.
- Where a lab mentions international programmes (for example IGCSE or A Level), it means the topic is similar; it is not an official alignment with those programmes.
8. AI helpers
The Ask the lab guide button and the AI lesson-plan tool write their answers with artificial intelligence. AI answers are drafts: they can contain mistakes. Teachers must read and correct an AI lesson plan before using it, and students should check AI explanations with their notes or teacher. Do not type personal information (names, phone numbers, passwords) into these tools. They have daily limits so that they stay free.
9. Advertising and sponsors
The site may show advertising from Google AdSense to cover its costs. Sponsored labs or messages are clearly labelled. Advertisers and sponsors do not decide the educational content.
10. Limits of our responsibility
The site is offered free and “as it is”. We do our best to keep it available and correct, but we cannot promise that it will always work without interruption, and we are not responsible for exam results or for decisions taken using the site. Nothing in these terms limits rights that you have under the law of Rwanda.
11. Changes and law
We may update these terms; the date at the top shows the latest version. These terms are governed by the laws of the Republic of Rwanda.
12. Contact
For any question, send a WhatsApp message to 0788 804 242 or an email to [email protected].
See also: Terms and conditions · Refund and delivery policy · Privacy · About us