In several early episodes Wally stepped in and told the parents about some trouble Beaver was in and Beaver did the same.

Can we list the times they helped out each other?

Wally told his parents how Beaver was kicked out of band so Beaver wouldn’t have to pretend he still played clarinet. Ward said they couldn’t go to the concert. Beaver was relieved.

Anyone?

Wally stepped in when Beaver told him about Eddie and the hypnosis gag.

Also when he thought Eddie changed Beaver's report card.

Good ones. That’s when Wally physically came to Beaver’s aid and not just tell Ward and June.

In Pet Fair Wally went downstairs to tell his parents that Beaver told his class he had a parrot. June makes Ward go get him a parrot. Nowadays if the wife told the husband to go rent a parrot he’d say you do it.

What about Beaver Becomes a Hero? Did Wally talk to W&J about Beaver getting in over his head?

Wally told his parents how Beaver was kicked out of band so Beaver wouldn’t have to pretend he still played clarinet. Ward said they couldn’t go to the concert. Beaver was relieved.

And similarly, when Beaver was cut from the basketball team after the first practice (by "mutual agreement"). Ward knew about it because he stopped by to watch the team practice but Wally still told Ward that Beaver was upset so Ward would't be too upset with him. Of course Ward was understanding.

How about the time Beaver told his parents why Wally was so upset about the dance because he couldn’t do the cha cha. Ward got Wally a quick lesson.

Beaver told Ward he (Ward) shouldn't have yelled at Wally about shaving, in front of Eddie. To make up for it, Ward told Floyd the Barber to make a big deal out of giving Wally a shave, in front of all they guys.

A couple of other times when Wally helped Beaver:

(1) In the episode we talked about the other day, where Beaver bought a girls' sweater, and made up a story about it being stolen. Wally stepped in to explain that it was a girls' sweater.

(2) And, in one of the early episodes, when Beaver didn't want to go to the all-girl party, and Wally explained the situation to June.

Poor Beaver was already at the party so it was too late. He did see Mr. Dennison who showed him his gun collection.

In The Pipe before Ward could really punish Wally for smoking, Beaver confided it was he who smoked the pipe.