Brand new Pi3 won't boot after first use

Help. Bought my daughter the Pi3 kit for Christmas. Followed the instructions and had fun with the blinkit then shutdown. We haven’t been able to get it to boot/turn on since. The green led just won’t come on at all.
As you can imagine this is incredibly frustrating!

Proper shut down from the Menu? Micro SD card fully seated?
Have a look see here,

Yes shutdown from the menu. No reason to think it didn’t do so fully. SD card properly inserted. I’ll check out that thread. Thanks for the response

I believe, if you take the SD card out, you should get a steady green LED. I do on my Pi A+ if I accidentally eject the card. It has the click lock holder. That would tell you if you had power going to the Pi. Kind of sounds like the power pack has failed?

Certainly worth trying with any other micro USB power supply you might have handy- although most will not be sufficient to power the Pi long term they might get the green LED to light.

Also, try removing the Blinkt! from the header, and make sure nothing metallic has snuck in/around the Pi that might cause a short.

Another option is to redo your Micro SD card. Just in case it got corrupted. Does the RED LED come on? That will tell you its at least getting power. I’ve been playing with my Pi Zero’s lately and forget that the other Pi’s have two LED’s A Red and a Green. The Zero only has the one Green LED. If the Red is coming on its likely not a power issue. No Green means no boot.