The best free homeschool science resources are not printable worksheets. They are complete video courses, university-built simulations, and real research projects that put your teenager’s data next to professional scientists’. Here is what is worth a slot in your week.
Full Courses and Textbooks
- OpenStax — peer-reviewed textbooks for biology, chemistry, and physics, free as PDF or online, with the same scope as a paid high school text
- CK-12 — flexbooks by grade band, with built-in practice sets
- Khan Academy — biology, chemistry, and physics sequences with checkpoints
- MIT OpenCourseWare — overkill for most, excellent for an advanced grade 11-12 student
For a credit-track course, an OpenStax book plus a lab log is genuinely sufficient. That combination costs nothing and stands up to review.
Simulations and Virtual Labs
- PhET — circuit building, gas behaviour, and optics simulations that behave like real apparatus
- HHMI BioInteractive — short films and data activities on evolution, ecology, and genetics
- Exploratorium — activity guides with clear explanations
Simulations are best used for what is slow or impossible at home: circuits that behave properly, or changes over geological time.
Printables and Reading
NASA and NOAA both publish free classroom guides, and many state geological surveys mail free maps. Your library’s interloan system will get you most popular science books within a week — use it before buying anything.
Beware the printable-worksheet economy. Colouring sheets and word searches feel productive and teach almost nothing. If a resource cannot point to an observation, a measurement, or an explanation, it is filling time rather than teaching science.
Citizen Science Projects
This is the most underused category and the one teenagers take seriously, because the data goes somewhere real.
| Project | Topic | Age | Commitment |
|---|---|---|---|
| eBird | Bird distribution | 10+ | 15 min weekly |
| iNaturalist | Species identification | 8+ | Whenever you see something |
| CoCoRaHS | Rainfall measurement | 8+ | Daily, 2 min |
| GLORP / GLOBE | Environmental data | 12+ | Monthly |
| Zooniverse | Classifying real images | 12+ | 30 min sessions |
Museums, Libraries, and Parks
Most science museums offer free or discounted homeschool days, often with a structured programme you can log as instructional time. State parks frequently run junior naturalist schemes with a certificate at the end — cheap motivation for grades 3-6.
Ask the Reference desk two questions most families never ask: whether the library has a museum-pass programme, and whether it subscribes to any science database you can use from home. Both are usually free with a card.
A Free 12-Week Plan
| Week | Topic | Free resource | Hands-on task |
|---|---|---|---|
| 1-2 | Classification | iNaturalist | Identify 20 local species |
| 3-4 | Matter | PhET states of matter | Density tower |
| 5-6 | Weather | CoCoRaHS | Build a rain gauge |
| 7-8 | Circuits | PhET circuit kit | Foil circuit on card |
| 9-10 | Plants | OpenStax biology ch. on transport | Celery and coloured water |
| 11-12 | Astronomy | NASA guides | Month-long moon log |
How to Vet a Free Resource
- Who published it — a university, museum, or agency beats an anonymous site
- Is there a date, and is it recent enough for the topic
- Does it ask the child to do something, or only to read
- Is there an answer key or worked example you can check against
Free homeschool science resources work best as a spine you add experiments to, not as a complete programme. Pair one with a notebook and a weekly hands-on session and you have a real course.
One warning: free material is rarely sequenced. You are the scope-and-sequence, so write down the twelve topics you intend to cover before September, and check off the weeks as you go. That list is the curriculum.
Keep Exploring
- Is homeschool science enough? — scope and sequence
- A weekly science experiment plan — fitting it into the schedule
- Homeschool science without a lab — equipment you already own
