The pump can be a much more flexible with handling control, then insulin injections...
Some advantages
She will always have her insulin with her
She can change delivery of basal rates to match her needs, most pumps come with 5 programable basal profiles, she could set up a profile for a normal school day, PE days, weekends/holidays..
If she eating with friends, no worries about whether to inject there and then or retreat to somewhere quite!!
Is she decides to have an after, or a pizza type meal where you would either have to another injection or split to cover the meal it's all a case of pressing buttons and perhaps choosing which bolus suits best..
She can tempory adjust her basal rate up or down, by using the TBR function on pumps to better meet her needs...
She can adjust her basal rate, by the hour (some pumps I think now have this at 1/2 hour interviews)
As her body changes from child to womenhood she be more able to keep up with the effects of changing hormones..
How many of the above can you do with injections?
I know that you say for the last year she has shyed away from the idea of an insulin pump,but maybe that was because she wasn't ready for one, and the change now is being a year older and a year wiser she feels now is the right time to get one..
I would say is if she wants one, then let her go for it... At the end of the day if she doesn't like it then she can easily go back to injections and you've been the best mum because you've given her a choice and allowed her to make it..