middle school o-line calls

To what extent do you think middle schoolers are capable of making o-line calls? I plan to severely limit them, but would like to get the kids used to making good presnap reads and communicating in relation to defensive adjustments. We are primarily an i formation power running team, and the primary calls i am thinking of instituting are for combo blocks, double teams, down blocking and cross blocks for the side of the line where two of my more cerebral guys play. Any thoughts/ideas/tips would be most appreciated.

Thanks in advance...