9yo Son Interested but Help Needed

I saw an ad on Instagram from USA Lacrosse about a free clinic, no equipment or experience necessary. We’ve been doing rec soccer and baseball but we were looking for maybe something new to try so I registered my son and he had an absolute blast, so much so that he asked to sign up as soon as the clinic ended. He even asked the clinic lead if he could keep his stick, which came from a big box of shipped youth sticks from USA Lacrosse I guess because it has that branding, and to the instructor’s credit he said he didn’t mind a stick walking away with someone who loved it.

Since then we found a local 10U rec team to register him with for spring play.

My big question is how do I continue to foster this interest and maybe practice with him between now and February when the season starts?

We tried cradling practice with a tennis ball but either we stink (entirely possible) or the ball is too light because it went flying. We’ve also tried throwing the tennis ball at the house and catching it but the bounce back is iffy.

I ordered a SwaxLax practice ball in hopes that might be better?

Anyways, I’m so out of my depth here. I’ve never played lacrosse, let alone watched a second of it. D Poles, stringing, head types, even the positions (which I thought might be close to soccer) sound like foreign phrases.

TL;DR: 9yo son wants to play lacrosse. How do I help him practice, stay interested, and both of us learn more?

Sincerely, Struggling Dad