If you can't afford a heavier package, I think that you should fish whatever you've got. Schoolies should be not be much of problem on that rig. A big fish would require some skill to bring in quickly, but good anglers quickly land large fish on relatively light tackle all the time. Don't fight the fish off the tip of the rod, and you should be ok. You will learn alot...like you need a heavier rod.
Problems you will run into: you will not be able to fish many of the most effective flies. You will be shut out if it gets windy. Your reel is probably going to need alot of TLC because it is probably a fresh water reel. You will not be able to cast the faster sinking lines.
I recomend that you fish small bucktails and flat wings(up to a few inches). They are easy to cast. For that rig, I would stay away from lead eyes and epoxy type flys. They might be too heavy for that rig. Good luck.
One cast can change your day...maybe your life.