ka April Highlights and 2025 AoPS Online Class Information
jlacosta0
Apr 2, 2025
Spring is in full swing and summer is right around the corner, what are your plans? At AoPS Online our schedule has new classes starting now through July, so be sure to keep your skills sharp and be prepared for the Fall school year! Check out the schedule of upcoming classes below.
WOOT early bird pricing is in effect, don’t miss out! If you took MathWOOT Level 2 last year, no worries, it is all new problems this year! Our Worldwide Online Olympiad Training program is for high school level competitors. AoPS designed these courses to help our top students get the deep focus they need to succeed in their specific competition goals. Check out the details at this link for all our WOOT programs in math, computer science, chemistry, and physics.
Looking for summer camps in math and language arts? Be sure to check out the video-based summer camps offered at the Virtual Campus that are 2- to 4-weeks in duration. There are middle and high school competition math camps as well as Math Beasts camps that review key topics coupled with fun explorations covering areas such as graph theory (Math Beasts Camp 6), cryptography (Math Beasts Camp 7-8), and topology (Math Beasts Camp 8-9)!
Prealgebra 1
Sunday, Apr 13 - Aug 10
Tuesday, May 13 - Aug 26
Thursday, May 29 - Sep 11
Sunday, Jun 15 - Oct 12
Monday, Jun 30 - Oct 20
Wednesday, Jul 16 - Oct 29
Introduction to Algebra A
Monday, Apr 7 - Jul 28
Sunday, May 11 - Sep 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Wednesday, May 14 - Aug 27
Friday, May 30 - Sep 26
Monday, Jun 2 - Sep 22
Sunday, Jun 15 - Oct 12
Thursday, Jun 26 - Oct 9
Tuesday, Jul 15 - Oct 28
Introduction to Counting & Probability
Wednesday, Apr 16 - Jul 2
Thursday, May 15 - Jul 31
Sunday, Jun 1 - Aug 24
Thursday, Jun 12 - Aug 28
Wednesday, Jul 9 - Sep 24
Sunday, Jul 27 - Oct 19
Introduction to Number Theory
Thursday, Apr 17 - Jul 3
Friday, May 9 - Aug 1
Wednesday, May 21 - Aug 6
Monday, Jun 9 - Aug 25
Sunday, Jun 15 - Sep 14
Tuesday, Jul 15 - Sep 30
Introduction to Algebra B
Wednesday, Apr 16 - Jul 30
Tuesday, May 6 - Aug 19
Wednesday, Jun 4 - Sep 17
Sunday, Jun 22 - Oct 19
Friday, Jul 18 - Nov 14
Introduction to Geometry
Wednesday, Apr 23 - Oct 1
Sunday, May 11 - Nov 9
Tuesday, May 20 - Oct 28
Monday, Jun 16 - Dec 8
Friday, Jun 20 - Jan 9
Sunday, Jun 29 - Jan 11
Monday, Jul 14 - Jan 19
Intermediate: Grades 8-12
Intermediate Algebra
Monday, Apr 21 - Oct 13
Sunday, Jun 1 - Nov 23
Tuesday, Jun 10 - Nov 18
Wednesday, Jun 25 - Dec 10
Sunday, Jul 13 - Jan 18
Thursday, Jul 24 - Jan 22
MATHCOUNTS/AMC 8 Basics
Wednesday, Apr 16 - Jul 2
Friday, May 23 - Aug 15
Monday, Jun 2 - Aug 18
Thursday, Jun 12 - Aug 28
Sunday, Jun 22 - Sep 21
Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)
MATHCOUNTS/AMC 8 Advanced
Friday, Apr 11 - Jun 27
Sunday, May 11 - Aug 10
Tuesday, May 27 - Aug 12
Wednesday, Jun 11 - Aug 27
Sunday, Jun 22 - Sep 21
Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)
AMC 10 Problem Series
Friday, May 9 - Aug 1
Sunday, Jun 1 - Aug 24
Thursday, Jun 12 - Aug 28
Tuesday, Jun 17 - Sep 2
Sunday, Jun 22 - Sep 21 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Monday, Jun 23 - Sep 15
Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)
AMC 10 Final Fives
Sunday, May 11 - Jun 8
Tuesday, May 27 - Jun 17
Monday, Jun 30 - Jul 21
AMC 12 Problem Series
Tuesday, May 27 - Aug 12
Thursday, Jun 12 - Aug 28
Sunday, Jun 22 - Sep 21
Wednesday, Aug 6 - Oct 22
Introduction to Programming with Python
Thursday, May 22 - Aug 7
Sunday, Jun 15 - Sep 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Tuesday, Jun 17 - Sep 2
Monday, Jun 30 - Sep 22
Some users don't want to learn, some other simply ignore advises.
But please follow the following guideline:
To make it short: ALWAYS USE YOUR COMMON SENSE IF POSTING!
If you don't have common sense, don't post.
More specifically:
For new threads:
a) Good, meaningful title:
The title has to say what the problem is about in best way possible.
If that title occured already, it's definitely bad. And contest names aren't good either.
That's in fact a requirement for being able to search old problems.
Examples: Bad titles:
- "Hard"/"Medium"/"Easy" (if you find it so cool how hard/easy it is, tell it in the post and use a title that tells us the problem)
- "Number Theory" (hey guy, guess why this forum's named that way¿ and is it the only such problem on earth¿)
- "Fibonacci" (there are millions of Fibonacci problems out there, all posted and named the same...)
- "Chinese TST 2003" (does this say anything about the problem¿) Good titles:
- "On divisors of a³+2b³+4c³-6abc"
- "Number of solutions to x²+y²=6z²"
- "Fibonacci numbers are never squares"
b) Use search function:
Before posting a "new" problem spend at least two, better five, minutes to look if this problem was posted before. If it was, don't repost it. If you have anything important to say on topic, post it in one of the older threads.
If the thread is locked cause of this, use search function.
Update (by Amir Hossein). The best way to search for two keywords in AoPS is to input
[code]+"first keyword" +"second keyword"[/code]
so that any post containing both strings "first word" and "second form".
c) Good problem statement:
Some recent really bad post was:
[quote][/quote]
It contains no question and no answer.
If you do this, too, you are on the best way to get your thread deleted. Write everything clearly, define where your variables come from (and define the "natural" numbers if used). Additionally read your post at least twice before submitting. After you sent it, read it again and use the Edit-Button if necessary to correct errors.
For answers to already existing threads:
d) Of any interest and with content:
Don't post things that are more trivial than completely obvious. For example, if the question is to solve , do not answer with " is a solution" only. Either you post any kind of proof or at least something unexpected (like " is the smallest solution). Someone that does not see that is a solution of the above without your post is completely wrong here, this is an IMO-level forum.
Similar, posting "I have solved this problem" but not posting anything else is not welcome; it even looks that you just want to show off what a genius you are.
e) Well written and checked answers:
Like c) for new threads, check your solutions at least twice for mistakes. And after sending, read it again and use the Edit-Button if necessary to correct errors.
To repeat it: ALWAYS USE YOUR COMMON SENSE IF POSTING!
Everything definitely out of range of common sense will be locked or deleted (exept for new users having less than about 42 posts, they are newbies and need/get some time to learn).
The above rules will be applied from next monday (5. march of 2007).
Feel free to discuss on this here.
Alice has a map of Wonderland, a country consisting of towns. For every pair of towns, there is a narrow road going from one town to the other. One day, all the roads are declared to be “one way” only. Alice has no information on the direction of the roads, but the King of Hearts has offered to help her. She is allowed to ask him a number of questions. For each question in turn, Alice chooses a pair of towns and the King of Hearts tells her the direction of the road connecting those two towns.
Alice wants to know whether there is at least one town in Wonderland with at most one outgoing road. Prove that she can always find out by asking at most questions.
Let be any point on side of .Let and be points on and such that and respectively. Prove that the locus of circumcenter of is a line.
Prove without using moving points :D
Andrew and Barry play the following game: there are two heaps with and pebbles, respectively. In the first round Barry chooses a positive integer and Andrew takes away pebbles from one of the two heaps (if is bigger than the number of pebbles in the heap, he takes away the complete heap). In the second round, the roles are reversed: Andrew chooses a positive integer and Barry takes away the pebbles from one of the two heaps. This goes on, in each round the two players are reversing the roles. The player that takes the last pebble loses the game.
In the non-isosceles triangle , is the midpoint of side , is the midpoint of side , is the midpoint of side .The line(different from line ) that is tangent to the inscribed circle of triangle and passing through point intersect line at .Define similarly.Prove that are collinear.
Suppose you have an grid with rows and columns, and each square of the grid is filled with a non-negative integer. Let be the average of all the numbers in the grid. Prove that if the there exist two identical rows (meaning same numbers in the same order).
3 girls and 4 boys must be seated at a round table. In how many distinct ways can they be seated so that the 3 girls do not sit next to each other and there can be a maximum of 2 girls next to each other. (The table is round so the seats are not numbered.)
Note that this is in no way trying to slander people who qualified through states with lower cutoffs. It is to compare cutoffs from 2022-2025. Qualifying nationals in any state is an exceptional achievement.
All credit goes to @peace09 for compiling previous years.
Additionally, thanks to @ethan2011/@mathkiddus for the template.
Tier colors have been removed as per the nationals' server requests.
For those asking about the removal of the tiers, I'd like to quote Jason himself:
[quote=peace09]
learn from my mistakes
[/quote]
In the diagrams below, switches A, B and C work independently of each other. The probability that any given switch is closed is 0.9. Current can only flow through a switch if it is closed. Work out the probability that the current can flow from on end to the other end of the circuit. Diagrams attached below
When I had less than 25 posts on AoPS, I saw many people create threads about them getting 1000th posts. I thought I would never hit 1000 posts, but here we are, this is my 1000th post.
As a lot of users like to do, I'll write my math story:
Daycare
I figured out I loved math when I was in daycare at the age of around 4. At the end of the "school year," I was already skip counting by 9s until 90!
Preschool
Ngl, during my one year at preschool, my math level probably got worse.
Kindergarten
My practice of skip counting from daycare was paying off. We were doing this activity where we counted items in rows and columns, but I could just multiply as a shortcut. I also started grinding Beast Academy!
Which at the time didn't have Level 1
First Grade
I finished all of Beast Academy. Yes, including Level 5. Then, I started grinding khanacademy.
Second Grade
I learned how to multiply and divide fractions on khanacademy. Other than this, my second grade year was insignificant.
Third Grade
Same as preschool, ngl, during this year, my math level got so much worse.
Fourth Grade
I figured out that one of my classmates was in the Intermediate Algebra class, and I wanted to be more like him, so I started doing AoPS. I started off with Prealgebra, which was pretty easy overall. This was when I started to realize I hated graphing.
Fifth Grade
My classmate from fourth grade was taking the "High School Math Contests" course on AoPS, so this year, I decided to take both the "Introduction to Algebra" and the "Introduction to Geometry" classes.
Sixth Grade
I started taking the "Intermediate Algebra" course on AoPS. At around week 14, my dad thought that I wasn't ready for this class, so he enrolled me in the "Introduction to Counting and Probability" self-paced class because if I'm being honest here, I'm worse at Counting and Probability than I am at Algebra 2. This is where I am now. :)
In conclusion, AoPS has helped me improve my math. I have also made many new friends on AoPS!
Finally, I would like to say thank you to all the new friends I made and all the instructors on AoPS that taught me!
Minor side note, but
Sorry if this was uninteresting or smth like that. I am not responsible :) :evilgrin:
yeah, bruh you cant call the three that you got wrong on target sillies. maybe like 1 or 2
I put 2025 for subset problem cuz I was being goofy, I put 13.5 instead of 27/2, and I got both leg lengths correct on the right triangle I just Pythagorean theoremed wrong
2 problems before 20: calculation errors
problem 20: wrote the length of the altitude (12/5) instead of the requested length
problem 26: idk what i was thinking, i put 4
problem 27: cheesed it using a rectangle but still messed up (got a radical) and ran out of time while fixing it
problem 30: not talking about it
problem 8: overthought it and put 51/2
I had a really bad day on the competition and just blanked a bit
Indeed, I had the Spelling Bee (which is forty minutes apart from the Mathcounts testing center) which was exhausting and I was in a bad condition to take the state. The important thing is I made nats, which I (hopefully!) won't silly.
Didn't want to judge before I got the test, but here is every silly I made, or questions that I could have easily gotten right
Sprint:
11) I forgot that that
14) I honestly don't know how I sillied this, but I think I put that or smth
24) I forgot to read "odd"
28) not a silly, but a genuine mistake
30) Rushing at the end of the test with little scratch paper, and probably like 10 arithmetic mistakes caused me to get this wrong, although it was easy in concept
Target
6) I had the correct answer, but I doubted myself, and I didn't want to check with like 5 seconds left. In an alternate universe, I could have easily gotten this one right
8) Overthought it and put 81/2, thought that I had to multiply by 3 since it was a group of three, but I forgot that you could take a running probability, and it doesn't have to be in packages of three. Borderline if you count this as a silly, but I'll count it, since I could have seen myself getting in right.
VERY disappointed in my performance in state, since I did so well in chapter 43), with only 1 SILLY (not necessarily a silly per se, but a question that I could have easily gotten right)!!! Most math contests I make like 3-4 sillies, so I thought if I continue my performance, I could have a decent shot at making nationals (I live in cali, so a "decent" shot for me is <5%). Nevertheless, my performance at state was very bad (for me), and I did not even make cdr. I got first in my chapter, and 2 people from my chapter made top 10, and one even got third! If I had the best possible score I could have gotten I would have gotten a 42, which would have putten me comfortably for cdr, although I still wouldn't have made nationals, but my main goal (realistic) goal was cdr. And before you say it's unrealistic to score almost the same in target and chapter, I know some people who boosted their score by like 5 points (I think). And even I went from a 41 (I think) on school to a 43 on chapter. Now, all of these things wouldn't really matter besides one crucial factor, I am in 8th grade, and this is my last year doing mathcounts. Mathcounts is what has gotten me into comp math, and I am forever grateful for the problems and experiences Mathcounts has provided me. I didn't do it as a sixth grader because I had never heard of comp math before, and I thought it was just another one of those "challenging" middle school math programs that ask, "WHaT iS ThE GreATeST 3 DiGiT INTeGer????!!?!!!" But when I saw my friend doing some mathcounts problems that were legitamately challenging, I decided to got, and oh boy did I love it. I tried out for the team in 7th grade, and I made it (partially my taking every test and memorizing all the solutions because my coach uses old tests for selection). I made it to chapter, where I won CDR!!!!! Winning CDR in chapter my first year was by far my proudest accomplishment in my comp math career, since I only just barely made CDR. But in 8th grade, I didn't practice as much as I did in 7th, so I guess I shouldn't be too disappointed in my score. But, I'm not really mad at how I did, but more of the fact that i don't get another shot to prove myself. So, to any seventh graders who are disappointed in their score in mathcounts, please remember that you have a whole year to practice and improve. But, I've met some of my best friends in mathcounts, so I guess I could say:
"The real mathcounts is the friends we made along the way"
- Abraham Lincoln
This post has been edited 1 time. Last edited by Existing_Human1, Yesterday at 6:14 PM