U.K. Family Visa w/ U.S. criminal record

Hi everyone!
Here's my situation...my husband just accepted a job offer in the England. We've been married for 16 years and have 3 children (under 12).
Last year, I was given a citation for shoplifting (7/9/15) under $100 (mistakenly left an item in my cart and they took it as stealing) I was never fingerprinted. since, I've never been in trouble before, I was given diversion. I took a class and "stayed out of trouble" for 90 days and my case was DISMISSED 2/2016
I have no convictions on my record.
Arrest and dismissal are there.
How does this read in the U.K.?
Do I consider it spent?
Do I declare it? I understand that the Rehab Act has changed but only has implemented these changes with tier 1 visas.
Would they deny me entry because of it?
Any advice and/or info would be greatly appreciated.

How does this read in the U.K.?
Do I consider it spent?
Do I declare it?

It must be declared. Using deception carries a 10 year ban.

I understand that the Rehab Act has changed but only has implemented these changes with tier 1 visas.

It applies to all applicants for visas now. Even previous visa applications are now checked to see if the applicant has used deception for a UK visa/entry to the UK, before. UKVI go back over at least a 10 year history now. There are plenty of posts from people saying they have had their ILR removed or been refused ILR, because of deception in a previous applicaton, so it is important to be honest.

I'm not sure how UKVI will view the timescale of your offence, before a visa will be issued.  ksand usually answers that. You could try looking back at some previous posts on here?

I'm not sure how UKVI will view the timescale of your offence, before a visa will be issued.  ksand usually answers that. You could try looking back at some previous posts on here?

As mentioned, you'll need to disclose it anyway and include all paperwork associated with it (along with your criminal record).

The first thing to determine is whether it's actually considered a criminal conviction or not. If it's not on your criminal record, then it may not be considered an actual criminal conviction and therefore shouldn't affect the visa decision anyway.

If it was a conviction, and it was non-custodial (i.e. you paid a fine, but no jail time), then as long as at least 12 months have passed, it won't affect the visa decision. But if it's been less than 12 months, it'll be a visa refusal.

See here for more information:
https://www.gov.uk/government/publications/when-can-i-refuse-on-the-grounds-of-criminality-rfl10/when-can-i-refuse-on-the-grounds-of-criminality#rfl103-when-can-i-refuse-on-the-basis-of-non-custodial-sentences

Last year, I was given a citation for shoplifting (7/9/15) under $100 (mistakenly left an item in my cart and they took it as stealing)

Reminds me of one time I went to ACE Hardware to get a new pre-made window screen. Went in, found it, measured about 5ft x 4ft so pretty big. Took it home. I must have been very distracted/stressed at that point in my life because within two minutes of getting home I suddenly realized I didn't pay for it! Freaked out, drove back to the store, walked in carrying the screen and went straight to the register. Nobody said anything or noticed. I guess this kind of thing can happen to anyone.