Mathplanet

Mathplanet is a free math learning site for students working through US high school mathematics. Its homepage offers "Free high school math courses - Pre-Algebra, Algebra 1 & 2, Geometry, plus SAT and ACT prep. All completely free." The site describes itself as "A free service from Mattecentrum," and the homepage explains that Mathplanet is run by Mattecentrum, a non-profit, which asks visitors to "Help us keep it free" with a donation button set at $20. There is no subscription or paid tier to describe: the homepage presents every course as completely free.

The About page sets out the aim: "to spread mathematical knowledge all over the world, completely free of charge." It is plain about the scope. "The educational material is focused on US high school maths," it says, and then adds, "However, since maths is the same all over the world, we welcome everybody to study math with us, for free." The homepage puts the reach at "Over 300,000 people learned math here for free this year."

Mattecentrum lists its other tools in the site header: Matteboken, an Arabic edition of Matteboken, and Webmatematik in Danish. Mathplanet is the English-language site of the group.

The math courses

The homepage lays the catalog out as six starting points, each with a one-line description:

• Pre-Algebra, "Build your foundation"
• Algebra 1, "Equations and functions"
• Algebra 2, "Advanced algebra topics"
• Geometry, "Shapes, proofs, and space"
• SAT prep, "Practice tests and tips"
• ACT prep, "Practice tests and tips"

The four math courses run from a pre-algebra foundation through Algebra 1 and Algebra 2 to Geometry, the sequence the About page calls high school math. Each course has its own overview page, and the site also offers a Math Playground and a separate collection of practice tests. The About page describes the exam side in one line: "We have also prepared practice tests for the SAT and ACT." So the SAT and ACT sections are practice material with tips rather than a taught exam course.

For a learner, this makes Mathplanet a self-study resource. A student who is stuck on a topic in class, or who wants to review before a test, can open the relevant course and work through it at their own pace, and a student facing the SAT or ACT can sit practice tests without paying for a prep course.

Programming in Python

The most detailed part of the site is a beginner course, Programming in Python, "adapted for Middle school or junior high school students." It assumes nothing: "You do not need any prior experience of programming, we will start from the very beginning." The course runs in five chapters:

• Thinking machines: how computers work, how they think and how we teach them to do new things, with lessons on getting started, Hello world, the Turtle module and Python variables.
• To remember: program code, the types of data there are and making programs adapt to what the user wants, with lessons on data types, interactive programs, errors ("When it goes wrong"), geometry and modules.
• Logic and choice: how computers use logic to choose between options, with lessons on logical conditions, more options, a game and simple repetition.
• Repeating code: loops, which the course calls "one of the most important pieces of the programming puzzles," with lessons on looping turtles, text, lists and following instructions.
• Real thinking: writing larger programs, breaking them down so they are easier to understand, what the subject of computer science is about, and building "our own AI," with lessons on functions, arguments, index, sorting and AI.

Each chapter is organized into tabs for the chapter text, prior knowledge, in-depth material and exercises. The exercise bank is long and sorted by difficulty level, Easy, Medium and Hard, with short checks such as "What gets printed?", "Will it work?", "Match the datatype", "What type of error?", "Infinite loop", "Correct if-statement" and "How long is the list?". Most of them ask a student to read a piece of code and predict what it does, which suits a beginner building confidence one concept at a time. A few exercise titles are still in Swedish, such as "Hitta tillbaka" (find your way back) and "Längd och summa" (length and sum).

The course closes with a short section on where programming is used: in computers, phones, video games, robots, headphones, cars and speakers; in websites that should look good on both small and large screens; in apps and games; in the large systems that let people pay and transfer money or that make electric power plants produce just as much power as needed; and as a hobby, such as having the lights turn off when the front door is locked. For further practice it links to outside resources, including a Real Python guide to the Turtle module, a Trinket Python page and several sites in Swedish such as Pythonlabbet and Kodboken.

Price and license

Everything on Mathplanet is free. The homepage says "All completely free," the About page says the material is offered "completely free of charge," and the site asks for donations: "Every contribution, no matter the size, has a significant impact on Mathplanet." The About page adds that the organization is "dedicated to offering a free, accessible platform for learning mathematics." The footer states that Mathplanet is licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International, which matters to a teacher or parent who wants to share the material with students. The site does not mention certificates, accounts or progress tracking.

Who it suits

Mathplanet suits a US high school student who wants free, self-paced review of Pre-Algebra, Algebra 1, Algebra 2 or Geometry, and a student who wants SAT or ACT practice tests and tips at no cost. Parents and homeschooling families get a free reference for the core high school sequence, and teachers can point students to it as extra practice. The Python course is a sensible first step for a middle school student, with short chapters, a start in turtle graphics and a long list of quick exercises graded by difficulty. Learners outside the US can use it too, as the About page invites.

The trade-offs follow from the model. Mathplanet is a free reference site rather than a tutoring service or a school platform, so a student works alone, without a teacher or live help. The math offer stops at Geometry, Algebra 2 and the two exam preps, so a student in precalculus or calculus will need another resource, and younger children are served mainly by Pre-Algebra and the middle school Python course.