AMC 8 Prep, for grown-ups
In short: practice for the AMC 8 math competition, in the browser. No account needed and no ads. Progress stays on this device, unless a grown-up turns on the optional Numberdale family account. Otherwise we receive only anonymous counts, and the problem reports your child chooses to send.
What it is
The AMC 8 is a 25-question, 40-minute multiple-choice contest for students in grade 8 and below, run by the Mathematical Association of America (MAA). AMC 8 Prep makes fresh practice problems in the style of the contest: every problem is generated on the device, with its own numbers and a drawn figure, and comes with a worked solution. Nothing is copied from real contests; real past papers are linked on the Art of Problem Solving wiki.
How it works
- Today's plan. About ten problems a day. Problems your child missed come back first, as a similar problem a few minutes later and as reviews one, three and seven days later.
- It adapts. Each topic has its own level. The next problem is hard enough to learn from but usually solvable; a right answer moves the level up, a miss moves it down. An optional 10-problem check on the first visit sets the starting point.
- Hints, Show me and Come back to it. A hint shows the key idea before answering; a right answer after a hint counts half, and the problem comes back for review. Show me gives the answer and solution without guessing, which is fine: it tells the page honestly what still needs work. Come back to it saves a problem for the end of the session, as on the real test.
- Sprints and past papers. A 12-minute sprint practices contest pace. For a full past paper, the problems open on the AoPS wiki (or on paper) and your child fills in the answer sheet here; the page scores it against that year's top 5% and top 1% cutoffs.
- Topics. Arithmetic, algebra, counting and probability, number theory, ratios and rates, statistics, geometry, and logic and patterns. More problem types are added every week.
Privacy
- Progress stays on this device. The name your child types, their answers, levels, reviews and past-paper scores are saved in this browser only. We never see them. Clearing this site's data in the browser erases them. Progress can also be moved by hand: the report page copies a progress code to paste into another browser.
- The family account (optional). A grown-up can sign in with a Numberdale family account (the same one for every Numberdale game, made at accounts.numberdale.com with an email address). A player added to the family then has their progress copied to our server, so it follows them to another device: their nickname, grade, answers, levels, reviews and past-paper scores, and a short summary the parents' page shows. Nothing is sold or shared, and a grown-up can remove a player or delete the whole account there at any time. Without signing in, nothing about the player leaves the device.
- No ads, no tracking across websites, and no cookies. We never ask for a child's real name, email, photo, voice or location.
- Anonymous counts. So we can tell which problems are too hard, too easy or confusing, the page sends a few anonymous counts to our server (api.numberdale.com): that it was opened today (once a day, with how many days since this device first opened it), that a session, the placement check, a practice test or a past paper was started or finished (with a practice test's score, and a paper's year and score; when a past paper follows practice tests, its score goes together with the practice-test average, so we can check how well practice tests predict), and, for each answer, the kind of problem, whether it was right, wrong, skipped or right after a hint, and roughly how long it took (up to a minute, one to two minutes, or longer). Nothing goes with them that could tell who practiced: no name, id, cookie, account, device, address or browser. We keep only the day's totals, for 400 days.
- Problem reports. Under each solution, "Report a problem with this question" sends us the problem's code (which rebuilds that exact problem), a reason such as "the answer looks wrong", and an optional short note of up to 300 characters. Please ask your child not to write names in the note; email addresses, links and phone numbers are removed by our server before a report is stored. Nothing else goes with a report. We keep reports for 180 days.
- A page counter. The page loads Cloudflare Web Analytics, a small counter from our host. It reports that the page was opened, the site that linked here, the country and the kind of browser, with no cookies, no local storage and no fingerprinting, so it cannot tell one visitor from another.
- The page's fonts come from Google Fonts. Like any website, requests pass through our host, Cloudflare. Our site does not keep request logs or IP addresses.
Questions
AMC is a trademark of the Mathematical Association of America. AMC 8 Prep is not affiliated with or endorsed by the MAA. If anything here changes, we will update this page and its date. Questions and ideas are welcome: hello@numberdale.com. AMC 8 Prep is made by Numberdale.