Not the easiest for the junior player as it’s mostly quite high for you. If you’re blowing hard (and hitting with big T’s to get the notes out, then some homework is needed first.
The challenge will be to get a smooth legato, and this will expose embouchure problems, the security of your hold on the flute and fingering issues. Make sure to finger middle D correctly, -top finger off!
For the younger player, this low scale is seriously challenging due to the little finger stretch to reach the Low C key safely (without touching D# or the trill keys).
The arrow indicates that you need to make sure to place the little finger back on its usual position, the D# key. This is so that you build a unified technique, not different versions of the same fingering (and the E will be properly pitched, not flattened). So, although C Major might be the easiest scale on a keyboard, it certainly isn’t for junior players on flute.
Two octaves of C Major throws all of the challenges together. Be strict about the ‘L’ (little finger) and the correct middle D fingering: you’ll be saving yourself a lot of trouble later on if you spend some time to get this right.
The biggest challenge of all will be breathing / phrasing.
As above, good discipline with the little finger moving between Low C key and D#: building a secure future – take your time.
Double trouble! Watch out for the little finger. And what about generating a solid tone through the two octaves? Much homework and attention to detail required here. Always apply a critical ear as the aim is to be a good musician, i.e. playing musically, a pleasure to hear.