You're lucky. Ngl, I'm a little jealous :/
Anyway, from reading the comments, I doubt those boys mean anything serious- and if it is truly 2nd graders, it is really nothing to really dwell on- I'm sure several people have had kids wayyyy younger hen them hit on 'em. Even I have! But it's nothing to worry about. However, if these kids are older than you beware! If these are boys you personally know, just politely ask them to cut it out!