The theorem bears a Greek's name, but the Babylonians used the relation centuries earlier. Who discovers maths is a piece of history too.
Maths
RuitGrid
Maths you actually understand, from year 5 to the middle of secondary school.
OpenAges 10 to 16Free to start, then €4 a month
What it is
Ruit starts every topic from a question or a picture, not a formula. You practise straight away, get a hint when you are stuck and a worked solution, and then always a fresh variant.
What is there
- A learning path from numbers to linear functions
- Exercises checked on the spot, with a hint and a worked solution
- Examples from here: euros, Belgian cities, the train
How far along it is
OpenOpen and ready to use.
What it costs
You manage Kaft Plus on the Kaft website.
€4 a month or €36 a year
The learning path and the first 3 topics are always free.
Or every app together in the Kaft package: €8 a month or €69 a year, €471 a year less than everything separately.
Where Ruit meets other subjects
VAT, discounts, inflation, a growing city: percentages are the language we use for money and population.
A scale of 1 to 25,000 is simply a ratio. Understand it and you can measure on the map how long the walk is.
An experiment gives you numbers, a graph turns them into a story. The same skill, in two subjects.
A half note, a quarter note, an eighth: filling a bar is doing fractions without noticing.
Every place in a binary number is a power of two. Understand powers and you can read the computer's language.
Interest is a percentage that comes back every year. With percentages you see what a loan really costs.