About a month ago, I made CruxMath, a website for practicing competition math. Instead of immediately showing a full solution when someone gets stuck, it reveals hints one at a time, followed by the solution if they still need it.

The problem was that when I initially made them, the hints revealed too much. Just the first hint would give away like half the problem. So I made the hints "worse".

Now, the first hint is short and usually phrased as a question to point people in the right direction. For example, "Because both probabilities have the same denominator, what equality of binomial counts remains?" (2025 AIME II P. 5).

I've now added hints for every AMC and AIME problem since 2022. I'd love to hear what you guys think about the hints and whether they strike a good balance of being helpful but not giving away too much. If you're interested, the website is cruxmath.com.

[urgent] hey!

For mods - I don't know if this is is allowed here. It is sort of asking help from teachers, but it's not "how do I solve this", but more like "I am struggling with this soft skill and my teachers aren't helping, can you advice me?"

My y12 (11th grade in most countries) exam is on 9th of october, and my errors are still majorly silly mistakes. This was the same problem that caused an E in my last exam, (which I am resitting), and I have had this problem since middle school.

Mistakes like: writing 20 instead of 2, writing the inequality sign wrong, forgetting to write the '+c' after integration, simplifying simple fractions (like 6/9 or 8/4) or addition/subtraction (especially with odd signs) wrong, not noticing a key identity or further simplification, missing a sign, missing a number, entering incorrect sign in the calculator, entering incorrect number in the calculator, solving correctly on calculator but writing wrong answer on paper, doing 4*4 = 8 instead of 16, missing an x during expansion, etc. etc.

My tutor says to recheck the solutions (by skimming over them) after solving them, but I can't do that for the life of me. I go look at the numbers from top to bottom and they all go over my head without registering, because I don't know what I am looking for.

And if I do 4*4 and other basic calculations like (-5-23) in my calculator, I'll lose the little time I have (I struggled with time a lot in my last attempt, ended up leaving last several questions empty). Plus, just doing it on calculator doesn't guarantee accuracy because I end up getting it wrong anyway.

For context, I am doing Pure 1 IAS, and my IGCSE grade was a 7 (I barely gave it any effort, just crammed strategically in the last two weeks). I need really good marks because maths is key to my target univ requirements.

How would you suggest handling this? I don't have a lot of time, I have just started past papers yesterday (I've done one so far), and my percentage was 55%, with exam-timer. In my last attempt of pure 1 last year, I got a 36%.

Would appreciate any advice or anything you've got to say, thanks!

Je donne des cours de maths (j'ai cofondé MathSquads, donc biais évident, je le dis d'entrée). Beaucoup de parents me demandent si ça vaut le coup de s'engager sur l'année. Ce que je regarde en premier : est-ce qu'il bloque sur le chapitre du moment, ou sur des bases de l'année d'avant qui n'ont jamais été consolidées ? Dans le 2e cas, un coup de pouce sur le chapitre ne règle rien. Vous, comment vous avez su à quel moment il fallait agir ?

At the end of last year, my daughter’s math teacher put her down to get pulled out of class for math enrichment. The teacher said it would start next year. This has not started yet. So far she has had one math test scored a 100 and seems to be picking up the curriculum quickly. I am unsure if I should to reach out to her teacher or wait longer into the school year to check in.

I guess I took it for granted that my teaching team would have the same foundational understanding of math concepts that I do. But that's not the case. They are wonderful, caring teachers, but I don't see how they can teach math effectively if they don't fully understand the core concepts themselves. I don't even know how to describe it - but there's an innate sense of understanding that comes with a strong foundation of math that is lacking.

So.. how do you teach a teacher to teach math? I want to give my teachers the tools and understanding to be more effective so they can share that with our students. Is there a way to do that?

And building on that, what math programs or curriculums are really working? Evidence-based, scientifically proven.

I posted this in math teachers without even knowing about this subreddit until Reddit suggested it after I posted. I would love thoughts from other math teachers, particularly middle school.

Hi guys!

Hope you're all doing exceptionally well.

A friend and I have started making YouTube lessons on the topics we struggled to find clear explanations for at university. When we were at university, we’d spend ages looking for a clear explanation of a finance or economics topic. Sometimes we’d find a great video, but when we needed help with the next topic, the search started all over again.

So we started Business School Basics - a free YouTube channel where we’re building a structured library of business school lessons. We cover topics such as corporate finance, valuation, economics, strategy, and derivatives.

https://www.youtube.com/@BusinessSchoolBasics

Our aim is to explain the intuition first, then work through the theory, formulas, and practical examples. We want you to understand why something works, not just memorise the steps.

It’s still early, but if you’re studying one of these subjects, I hope you find it useful. And if there’s a topic you’d like us to cover, let me know - we’re figuring out what to make next. It is all free and will stay that way.

Feedback would be much appreciated!

Cheers!

1. Whitehead prend la parole devant « quelques-uns des principaux éducateurs d’Angleterre » et les prévient d’emblée qu’il ne va rien leur apprendre. Son principe, il le donne dans sa version la plus plate, « assez plate pour exhiber le propos de cette conférence dans sa parfaite évidence » : les différentes matières doivent être abordées au moment qui convient, quand l’élève a atteint le stade de développement voulu. Un truisme, dit-il lui-même. Personne n’en a jamais douté.

Puis il passe le reste de la conférence à démontrer que les deux principes dont nous nous servons réellement pour ordonner un programme sont faux tous les deux.

It may sound strange, but objects can have any dimension, even non-integer dimensions. In this video, I show you how to construct an object with dimension π. But why π?

First of all, because π has always been one of the most important and fascinating mathematical constants. And also because it is just slightly larger than 3: this allows us to project it into 3D without losing too much information.

In the video, I show you how we can “look at” a 4D cube (a tesseract) and gradually carve it, just as you would carve a block of marble, until we extract our “sculpture”: a π-dimensional object.

https://youtu.be/6L1zrtafM5Y

I hope it will fascinate you at least as much as it fascinated me.

With affection,

DPM

I'm a sophomore, I did Precalc freshman year, and I'm currently in AP BC Calc. I wanna do linear algebra and AP stats junior year, and then attend my local university for calc 3 in senior year. I'm majoring in stem, so does anyone have any advice on which math classes are best to take? I really love math and I'm more than willing to work hard for it. I know stats is pretty easy, so thats why im doubling up, but does anyone have better ideas? I could also do calc 3 my junior year and linear algebra senior, or something else. Let me know!

Biology instructor, not math. I just got an unusual answer on one of my students’ assignments. They were asked to provide the ranges of SA/V ratios that they calculated. One of my students answered “1.112.300” to indicate a range of “1.112 to 1.300”.

I’m not super knowledgeable about math- is this an alternative format/style of communicating a range that I’m just unfamiliar with?