We use boards of various strengths for various breaks that our instructor ranks y-3. y boards are so weak that I've seen a holder, albeit a strong one, break them just trying to hold them for a break. 2s and 3s are strictly for adults and 3s almost only for kick breaks. The only exceptions to this are blue belts and black belts. With weaker boards kids are allowed to do side kicks and elbow strikes and with 1s they must do a stomp kick. Punches are absolutely out of the question.
We walk in a local Fourth of July parade. Two days ago I watched to white belts about 5 break boards after only 1 class because the boards are so carefully chosen.
As far as confidence, I failed a two board spinning back kick break at my blue belt test and have been more or less afraid to do even a simple side kick break ever since and I'm 17, although that was only about three weeks ago, imagine the effect a failed break would have had on me when I joined at 11.