Wanting instruction is different than wanting exposure. If he wants instruction, go to cheap, local college camps.
For exposure, keep this in mind: top D1s recruit starting in freshman year (or earlier!), but you have to have the measureable numbers that they want. Mid-major D1s might or might not recruit early; every other level recruits the summer after junior year. So, if as a soph he has D1 numbers, then go to showcases now; if not, wait.
For a catcher, the numbers they want to know are his pop time and his batting exit velocity. They also want to know whether he can catch and hit high-level pitchers. So, playing on a summer team that has good pitchers and plays high-level teams is important.
Do you know the pop time and EV already? If not, before you go to any showcase, you should measure those yourself now, and see if they are D1 numbers. If they are, then yes, showcase now. If not, save your time and money and don't go until his numbers are there, or spring/summer after junior year.
There are showcases (PBR, PG) where they put your numbers into their system and on their website. If your numbers aren't that great, they will be available to the world until you do another one of their showcases. PG is very expensive, PBR less so. There are other showcases out there (including Headfirst for high academic schools, plus many local ones) that are just "whoever is there will see you". Those are useful if you have something to impress whoever is watching.
PBR varies from state to state; you can look at OK and see if what they say about players in your state makes sense: