This year for Master B's birthday we painted hulk t-shirts and the boys loved it.
I thought it would be awesome for Fathers Day to get us each a plain white top and have an A image.
(a for awesome, a for a team, a for amazing etc...)
I did a quick Google search and came across an Avengers image (I had to make a few changes due to print quality and it wasn't really a circle or exactly what I wanted but it would do)
With the same process as the hulk tops- printing an image, cutting it out and using it as a stencil. I had black paint left over from the hulk tops. They were all pretty quick to paint.
The boys think they are awesome and Mr B loved his just as much and wore it all Fathers Day.
So simple and effective for the A team.