[Brian]

Doc, happy to be of assistance, and welcome to the club. :-)

The way our location services works is that you tap the 'nearby' button, and OmniFocus shows you the contexts that have locations attached to them, ordered from nearest to furthest.

(The solution necessarily has to work on the phone, because the Mac version of OmniFocus doesn't have the same ability to figure out where you're at - you just select the one(s) that are relevant to your current situation in the app.)

Here's how I'd set up your contexts:
Campus 1
Hospital
Home
Campus 3
A "Gym" parent context, with child contexts having the name of each specific gym.
Computer
Book
Bag
(and just for good measure) Phone

Still on the mac, set up your projects. Add a "remember to bring gym bag" action to your workout project, assigned to whatever context describes where you keep your gym bag. (Home?) Ditto for Book and Bag.

You can use the Inspector to make either individual actions or whole projects repeat, depending on your needs. If not every action in the project repeats, don't make the project repeat. :-)

Assign actions that require a tool to the context for that tool. Assign other actions to the specific locations that make the most sense.

Here's where we get tricky: assign actions that can be done at any gym to the parent "Gym" context. Assign ones that require a specific gym to the appropriate child context.

(If it makes sense, you can apply the same techniques to your other contexts: create a parent context to contain actions that can be done at any of the child contexts. I have a no-location "errands" context, with child contexts for grocery, drug, book, and music stores, for example.)

Now, sync the database over to the phone. You'll add location information here. I'd do as follows.

Phone - always available
Campus 1, Hospital, Home, Campus 3 - street address of each.
Gym - parent context gets a business search that looks something like this:
name of gym 1 OR name of gym 2 OR name of gym 3

Enter the name of each gym with a capitalized OR between them. Type carefully, because it can be difficult to edit business searches; I wrote that up as a bug. If you make an error, you may need to blow the search away and start over.

For best results, don't enclose the gym names in quotes, and use google maps on your Mac to verify that the name you're entering gets the results you expect. (Enter the name of the gym with the appropriate zip code - does google find the gym you expect?)

Each child gym context gets the street address of the specific gym they're for.

Computer, Book, and Bag don't get locations associated with them; if you have that resource available, you look in that context. If you don't have it with you, you don't check that list.

Here's how this will all work. You're out and about. You hit the "Nearby" button in OmniFocus on your iPhone. You'll see the contexts that are closest appear at the top of the screen, with things getting further away as you scroll down.

You should see all the "Gym" tasks and the tasks for the specific gym that's nearest to you appear one after the other in your list. Further down in the list, you'll see the tasks that are specific to the other two gyms.

Does that make sense?