Personally, I don't think it was so much testing you as not really knowing what you want yet.
I didn't get how long you've been attending this class?
I attend one class, in particular, where I feel so sorry for the participants. I attend another class as well that is much better, but the first one is more local and it has what I need - other dogs and people for distraction, a roomy place to work, etc. It's a bit of a hard-ass class where the instructor is too hard on the dogs and on the people, IMO, and we don't use treats. But it's also a class that is trying to train the general public and they know they only have 10 weeks to try to get it in their heads, whereas my other class is with an obedience trial judge and we bring dogs along more slowly. The goal is different - the club is trying to create well behaved dogs in public in 10 weeks, the obedience judge is trying to bring dogs along for obedience trials ... eventually.
And that's the huge difference between me and the other people in the local class. They are training for 10 weeks (maybe) and I'm training for life. So, no matter what class you're in, you need to develop that attitude. For me, even in my local class, it's not about keeping up or doing exactly what I'm told but doing what is right for my dogs in the long haul. I know what they need because I've been training for a long time, and that's where it gets really hard on the novices that don't know when to stand up for themselves and who are trying really hard to keep up.
For instance, I started novice classes with Shelby in April at my local class. We just completed week 7 of 10 weeks. The instructor expected the dogs to be sitting on command and when we stop a long time ago, and she has people popping their dogs if they don't comply. Now, I'm not averse to popping *if* the dog understands the command but I haven't really pushed it with Shelby and I know she doesn't know it. Besides that, I'm still cupping her into the position I want because I know that Dobermans love to do the rockback sit and I want her to be firm on learning a tuck sit right up beside me. The instructor saw me doing that and remarked that Shelby was being really defiant that night. I right out said no, she's not. She doesn't understand the command yet and I have a method to my madness because like I said, I'm training for life, not for 10 weeks.
Anyway, it seems like this is a new class for you and as others have said, it seems much too early for lunge line work. Stays should be solid within leash length before you go off to a distance. It makes me wonder if it's more about the sale of lunge lines than about doing what's right for the dogs.
However, it is a lesson to you to pay more attention to what Bumpy is doing and when he gets to cones and cars, there is the place for your "leave it" command again.
Attention training involves getting the dog focused on your face, watching you. It's so easy to do. Use your treats, hold it up to your eyes and ask the dog to "watch me" or just "watch". When he makes eye contact, treat him. Do this quickly, and then gradually lengthen the time that he makes eye contact with you. When he becomes distracted, you should be able to say "watch me" and bring his attention back to your face. Games like "touch" are also fun for the dog and bring attention back to you. Essentially, you ask the dog to "touch" and put out your hand. Most will touch/sniff and you reward. When he gets consistent at doing that, you move your hand to different places and ask him to "touch". We use this later when we need dogs to move position like when they do the dreaded rockback sit and they are further behind than you like. You put out your hand, say "touch" and they come forward to where the hand is and you say "sit" to get them into a better spot. Later you can ask them to "touch" walls or fences or whatever.
Toys can also be used to build interest and make obedience fun. For eg. throwing a loved toy backwards between your legs so the dog has to run through to get it. Helps to build speed on recalls.