。。
It's a passing grade. Something like this is no big deal.
Literal
Passing-mark [copula-よ]. This-much big-deal thing not [copula-わ].
A confident, dismissive assessment. 及第点 (きゅうだいてん, 'passing mark/grade') is a somewhat formal academic term: 及第 ('passing') + 点 ('score'). よ at the end asserts confidently. これぐらい大したことないわ ('something like this is no big deal') uses ぐらい ('about this much / to this extent') and 大したことない ('not a big deal'). The sentence-final わ is the feminine assertive particle. The speaker is probably reassuring someone — or showing off — after completing a task.