I did this mistake when I first started training. It was embarrasing but somewhat funny. I'm sure the tower enjoyed it. This is at a small airport, where a TCA overlaps. For departing VFR to the training area your restricted to 2400 ft for about 10 miles unless you want to enter the TCA.

C172: Ground, this is cessna 172 GABC with info mike

Ground: GABC go ahead.

C172: Ground, GABC on North Apron request taxi to active for local north 2-4 thousand.

oops. I meant 2thousand 4 hundred!