Data Science
Python, statistics, and ML foundations — from first notebook to a model you can defend.
What you build: end-to-end projects on real datasets.
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Cohorts open · Data Science & DSA
Learn like a mentor is right beside you.
OnLearn turns a syllabus into a guided path — live classes, a concept tutor that actually teaches, and a lab mentor that reviews your code while you solve. You always know the next step.
This is
your AI mentor
It learns where you are, explains the concept in plain language, then sits beside you in the lab — reviewing your code as you write it. Not a chatbot bolted on; a mentor built in.
How it works
Three steps, one clear path.
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01
Enroll
Pick a track and we turn the syllabus into a guided line — module → topic → problem.
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02
Learn
Live classes plus a concept tutor that actually teaches, adapting to where you are.
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03
Practice
Write, run, and test in the browser while a lab mentor reviews your code as you solve.
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Pick where you're headed.
DSA
Data structures and algorithms with 440+ problems and a lab mentor on every solve.
What you build: interview-ready problem-solving instincts.
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A mentor that teaches, not tells.
YouMy binary search returns the wrong index sometimes. What's wrong?
MentorLet's look at your loop bound. When you write high = mid, the range can skip the answer. What value do you give high to start?
Youlen(arr).
MentorRight — so the last valid index is len(arr) - 1. Try that, and keep the loop while low <= high. Run it and tell me what you see.
Ready to start your path?
Pick a track, meet your mentor, and solve your first problem today.