I need advice how my pokemon could catch up?

Question

I was already planning my team and stuff in pokemon white and it seems that I'm going to have 5 pokemon after Castelia city. I need some advice on how my pokemon could catch up BY LEVEL - SO THEY COULD ALL BE AT AROUND THE SAME LVL? I'm currently in Pinwheel forest, training for Nacrene gym.
My team:

Sylvester(Servine) lvl 19
-Tackle
-Leaf Tornado
-Vine Whip
-Wrap

Zander(Blitzle) lvl 17
-Quick Attack
-Thunder Wave
-Charge
-Shock Wave

My future team:

Serperior
Zebstrika
Krookodile
Seismitoad
Archen
Haxorus

Thank you

Answer 1

Firstly, you can start raising a Tympole for your future Seiesmitoad, and use that as your third Pokemon (Found Pinwheel Forest Entrance). Try to evolve it before Castalia Gym, Leavanny will knock it out.

Secondly, a guy in the Pinwheel Fotest entrance will give you TM 94 Rock Smash. Teach this to a Timburr (Found once again in Pinweeel Entrance) and strike at Lenora's weakness. After you have beaten Lenora, catch a Sandile for future Krookoodile on Route 4. As your 5he pokemon for castelia Gym, raise a Darumaka rrom route 4 and use him to help the battle.

[EDIT]
The best place to train yout Pokemon before Lenora is deep in Pinwheel Forest (Bring Escape Ropes). Audino are EXELENT for traing.

Just Before Burgh, Desert Resort is great, especially Relic Castle. Get a fair idea of how far you can go while in there, youll need the info later in the game.

To beat Lenora, my reccomendation on your teams level is 23+, and for Burgh, 25+.

Comments

Thanks a lot for everything. I just taught my Zander Flame Charge, I din't really want any fire types, and I seriously need a flying type, so I will get an Archen for Fly and also he's a great pokemon. I thank you again for everything I'm sure it's gonna help me.

PS: I forgot to mention that I wanted to know how to train them so they could all be at the same level, not where or how to catch them. Thanks a lot anyways. :)
NEVERMIND I CHANGED MY TEAM THANKS