Infinite Problems.Real Feedback.
AI-generated coding problems on demand. Write and run real code in the browser. Get feedback on how you think — not just whether you passed.
How it works
The loop that actually builds skill.
Pick a concept. Get a fresh problem. Write real code. Understand where your thinking went right or wrong.
Fresh Problems
Every problem is AI-generated on demand. The well never runs dry.
AI-Generated Problems
A brand-new coding problem for your exact concept and difficulty level — every single time. Never the same question twice.
Runs Instantly
Write code in a real editor. Hit run. See which test cases pass and which fail — with input/output diffs — in seconds.
Feedback on your approach
The AI reviews how you wrote it — data structure choices, logic clarity, and what a strong solution actually looks like.
// AI Feedback
Your logic is correct, but using
ArrayList here adds overhead.
An array is more idiomatic
for fixed-size data — and what
an AP grader would expect. ✓
Track every concept
Every attempt is recorded. Your mastery per concept updates automatically — so you always know where to push harder.
See exactly where your students are struggling.
Create a class, share a join code, and watch. ParseString shows you which concepts your students haven't clicked yet — so you know what to focus on.
Overview
24 students enrolled
24
Students
enrolled
61%
Class Avg
mastery
3
At-Risk
need help
Class Performance by Unit
Needs Attention
Sam P.
22%7 days inactive
Tyler R.
31%High fail rate
Chris W.
54%Behind on Unit 4
21 other students are on track
Concept Mastery Map
Green means solid, red means revisit. Class-wide pass rates per concept, updated in real time.
Full Roster View
Every student's progress, pass rate, and last-active time — spot who's falling behind at a glance.
Read Their Feedback
See the AI coaching each student received. Understand the kinds of mistakes being made, not just the scores.
At-Risk Alerts
Students who haven't practiced or whose pass rate is dropping are flagged automatically.