my staff tried to bite us

i took my 11 month old staffy of the lead to let him run around as usual
he ran up to us and away, then out of the blue, he started barking and jumping off the floor trying to bite me and my stepson
he did this a few weeks ago, everytime i went to put him back on the lead he tried to bite us
got him on there after away and some shouting, he then walked ok on the lead and was fine when we got home

I think from your description it sounds like over excitement ??

Agree with Dave sounds like hitting the teenage stage and getting over excited

I would also say over excitement. When you go to the park, do you let him off the lead as soon as you get in there & then put it on again when you're ready to go home?

Sounds like overexcitement to me as well. You could try a long lead to let him have some freedom and still maintain control

i did let him of the lead straight away but he was ok this morning down the beach, now he feels sorry for himself

Tommy suffers from this excitement phase at the moment and can be a nightmare to handle so we make him sit and wait for a short while before we put his lead on to go out, when its time to put him back on the lead make him come and sit and wait, when you let him off the lead at home first sit and wait then release . He has to know that calm wins rewards , jumping around like a loon doesn't

What I've always done is a little bit of on lead training when I get to the park (heel work, sits, downs - all on lead), then I get him to sit & wait while I take the lead off - once the lead's off & he's sat for about 10 seconds I quietly & calmly say "Ok" and let him go.

Also, try putting the lead on for a few seconds several times during the walk - it'll stop him thinking that as soon as the lead goes on he's going home so the fun stops!

Agree with what Caryll said, that's what I do; I make Loki sit for a while before I let him go run wild, and if he's exciteable before we go out, I'll wait until he's calmed down. If you go when he's excited, then he'll associate excitement with a reward, I believe, so if you aren't already, definitely make sure he's pretty calm before taking him out or letting him off the lead.

Agreed, he is really amped. Stand your ground and correct it properly. No circumstance is a dog allowed to freely bite anyone, unless it is trained to do so and the situation the specific training is ABSOLUTLY needed for self preservation

Just excited, be patient and translate to him the behavior is not allowed, but not aggressive, Audi know you wouldn't do

Agree with above, excitement. Try some more training with him, use the SIT command when you want to put the lead on him. Take control of the situation with commands that he knows and build on that.