Welcome to the world of lasers. And props for good discretion 🍻 Maybe when they're a little older and understand the dangers you guys can get more involved. Building a laser would make for a great project with them.
that looks plenty bright to me! This is a multimode diode so the beam profile will be ugly to say the least... You can play around with the focus but the the beam will always be rectangular like that
Edit: It's a bit hard to tell on the brightness on a second glance. Do you have a LPM? Or...
If you can see light but it's way too dim, then I can think of two possibilities:
1) you already killed the diode
2) you're running the diode just below the threshold current (the diode can't draw enough current to properly lase)
You may have soldered to the wrong diode pin. It looks like the right pin is positive, the middle negative and the left is the case pin.
Edit: My next guess is you may have mixed up the polarity somewhere along the way. Do you have a multimeter? This will help troubleshoot polarity problems...