broccoli

bought a magazine with 2 free packets of seeds . 1 broccoli and other salad mix , no probs there so planted out they germinated but looked all the same (broccoli) so planted the salad mix again same result  now can u grow broccoli in tubs or should i just put in bigger pots and give most away as i now have an abundance of broccoli . sorry for long question ...
 thanks .

Broccoli is really an open ground plant, as it needs quite a bit of space.  I'd wait a bit for the first pair of true leaves to open on the seedlings (as Mitsy says, they do all look a bit similar) and then take it from there