There are tons of places to learn. I've viewed Cynthia Lin (great voice), Thethumbspro, Ukulele Mike, The Ukulele Teacher, James Hill's the Ukulele Way, and more. I learned to play several songs half way decently.
The problem is that the hit and miss nature of learning from different sources may be immediately fun, but doesn't help with the progression much.
When I decided to get serious, I signed up for Ukulele Underground University (UU+). I think Aldrine is an excellent teacher and he's got a great support group with him. It progresses like a regular class.
Beginner:
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Ukulele 100 (5 lessons, avg 20 min - from understanding your ukulele, through three basic chords (C/F/G7), basic strumming and timing.)
Ukulele 101 (12 lessones - avg 50 min - all the basics to play most songs using a few strumming patterns)
Basic Strum Course ( 6 lessons, avg 5 min - add to your strumming repertoire
It takes a couple of months to finish the Beginner courses if you're diligent. Afterward you'll be able to play 100's of songs at a reasonably decent level, plus a handful very well.
Intermediate:
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Ukulele 102 (10 lessons - avg ~20 min - exercises, picking, ear training, scales & tonal harmony, advance strumming, pulls/hammers and more)
Essential Chords course 2 (7 vids)
Fingerpicking basics (7 vids)
Soloing / flatpicking techniques (12 vids)
Blues (18 vids)
Hawaiian Ukulele (11 vids)
Music theory (10 vids of UU+, 14 Uke Minutes vids)
-- and lots more
Advanded:
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Ukulele 103
Advanced Soloing
Appled Music Theory
Advanced strumming
- lots more
There are alos numerous master classes with guest teachers like Imua Garza, Chris Salvador, Craig Chee, Kalei Gamiao, Bruce Shimabukuro, and more
As part of the Ukulele Underground University, there are weekly live lessons with interactive feedback, friday Aloha Play Alongs, Open Mic nights where you can show what you've learned, whiteboard requests to learn a new song, weekly webcam sessions with Matt Dahlberg and plenty more.
There are around 100 in depth song tutorials, most with separate play-along videos with chords displayed.
I'm very happy with my progress and the entire support network. I just go through the classes slowly, about 2 videos per week, and make sure to get a lot of practice in and do the video homework which you can post and get critiqued by one of the UU+ guys.
I still check out Cynthia Lin's and TenThumbsPro for some songs, and will likely do the Ukulele Way once I've complete the intermediate course. Just going through Ukulele 102 and the strumming courses, I've improved immensely.
The UU+ course isn't cheap, but there is a ton of resources and excellent access to the teachers. Ten years worth of instruction, ordered pretty well. Far more, and better laid out than anything else I've found. It's a proven path from beginner to very advanced. You can always do the 2 week free trial and see if it's for you.
BTW- I have nothing to do with the UU+ University, except that I joined and found it works for me.
I haven't tried The Ukulele Way, but it was my second choice. Less than half the price and it's friggin' James Hill! But it's also basically new, whereas the UU+ has been around for a decade and has had a chance to evolve with a ton of member feedback.