hi
We prefer to travel slowly so in 10 days would only do 3 destinations max, we find that moving too fast is really unsettling for children. Granada has a LOT to see and do, you could spend 4-5 days there, including Mombacho, Laguna de Apoyo... this is our blog on Granada>> https://worldoftravelswithkids.com/2017/07/24/11-great-things-in-granada-with-kids/ (hopefully that is allowed here. not sure.)

We haven't got around to writing about other places in Nica but 3 days at Morgans Rock would be awesome and then 3 days on Ometepe... its going to be a longish day of travel.. when there you could kayak with the kids, swim at the Ojo del Agua... You are right that it is pretty quiet though. I can't think anything that would be super interesting for small kids in Leon...

i don't like Las penitas much.

Central America is well much on the tourist trail and in the countries you mention - Guatemala, Nicaragua and Panama - you are likely to not only meet lots of travelers but also a ton of expats. 6 weeks is enough to get more than a glimpse of each country - how much you see depends on your preferred pace. All these are very much on the tourist trail:

Guatemala: Tikal, Chichicastenago, Lago Atitlan, Antigua
Nicaragua: Leon, Granada, Omotepe, San Juan del Sur
Panama: Bocas del Toro, Boquete, Panama City, Comarca de Kuna Yala

Incidentally, as a solo female traveler myself and having been to both, I can attest that it is quite possible to travel in both Honduras and El Salvador w/o encountering danger. If you are in western Guatemala, i recommend a short hop across the border to see Copan in Honduras. But to each their own comfort zone.

I would also not make a day trip from Jiquilillo to Leon. It is 3 hours by bus. Go from Jiquilillo to Leon and stay for a night and then go on to Managua for your flight. If you are really not into cities at all you could skip Leon. I often prefer nature to cities but I enjoyed Leon. Mind you, I also love volcanoes and there are some great ones near Leon so it was different for me.

I have not been to the Corn Islands but is there a reason why you are flying to Bluefields and not to Big Corn? If I am not mistaken there are only two boats a week from Bluefields to Big Corn, it takes 6 hours or so and can be a rough ride.

Ometepe is a not a party place. There are a few party hostels that you can easily avoid. It is a beautiful island. There are lake beaches but that might not be what you are looking for.

We always travel by bus and minibus. In minibuses you will always have a seat. Buses get crowded and you might have to stand for a while but I enjoy the hustle and bustle, the vendors, traveling with the locals...

I would also choose the beaches near Leon. Las Penitas is close and a nice village with a nice beach and fun waves (better for surfing/playing in the waves than swimming) and a nature reserve. I also like Jiquilillo, 3 hours north of Leon by bus. A rural area with deserted beaches and a nature reserve. Look at Rancho Esperanza and Rancho Tranquilo.

Corn Islands: I have traveled extensively in Nicaragua and have not yet been to the Corn Islands. They sound great and if you want the Caribbean island experience and you like snorkeling/diving that is where you would go. I have always found too much to do and see on the mainland. And you would fly there so I don't know if your budget allows that.

I would definitely go for 18 days. The longer the better. It would help to know if you like to hike. The volcanoes in Nicaragua are amazing.

You will enjoy Granada and Leon. I would add Ometepe Island. And maybe the northern highlands. If you do go to the Corn Islands I would say you need 4.5 days to have 3 full days there. Assuming no Corn Islands this is what I would do:
Ometepe (3 days). Two volcanoes (tough climbs but also great to just look at or to hike to the viewpoint), waterfall hike, nature reserve and ziplining (Chico Largo Adventure), monkeys, birds, kayaking, natural spring pool, lake beaches, rural communities (homestays possible).
Granada: a day for Granada, a boat or kayak trip through the isletas, active volcano Masaya in the evening (they drive you right to the crater). A day for Laguna de Apoyo. A day for volcano Mombacho (cloud forest).
A day for Leon. A half day trip to volcano Cerro Negro (short hike up, great views, active crater, board or run down). I highly recommend the overnight camping trip to volcano Telica (very impressive crater). Sunset tours possible too. A few days at the beach.

So you may have time for the northern highlands as well. Esteli: Somoto Canyon (swimming, tubing, rock jumping...). El Tisey (waterfalls, birds, hiking). Miraflor (you might enjoy a homestay there with a farmer).
And Matagalpa and Selva Negra for cloud forest, hiking, birds, coffee...

Or of course the Rio San Juan if you want rainforest and wildlife. I like Los Guatuzos. But it takes time to travel there.

You are correct...busy time of year so book ahead.

In Granada.....Las Isletas is very nice B&B.....nice pool and owners are cool and speak English and can help you as needed.

Here is car service you can use to get from MGA to Granada and then Granada to Mombacho and on to Ometepe from Mombacho....nice cars and good safe drivers. Email and he will confirm by email a No need to book this far ahead...you can do from corns. filix27@hotmail.es

It's a nice time of year as rainy season just over and all is green and lush.

Yes, 7 days is enough for the Corn islands for anyone. You'll be torturing your teenagers if you try to keep them there longer than that.

The whole area around Granada includes a lot of bewitching places, like Masaya volcano, Masaya market, Mombacho, and the Laguna de Apoyo. But from Granada, you're really close to getting to Ometepe island, and that's easily the most iconic place to visit in Nicaragua. No one can forget the view of the twin volcanoes on the island seen on the ferry trip to get there. It's a really rural place, and you have the opportunity for volcano hikes. Also there is kayaking on the Istiam river, bicycle trips, etc.

The most common route for backpackers going to and from Panama/South America, would be Panama City, San Blas, Bocas del Toro, cross border to Costa Rica at Sixoala caribe side (shuttles/boats between BDT and Pt Viejo.)

https://www.puertoviejosatellite.com

Surf on cairbe side varies by month, there are 3 areas, Pt Viejo Salsa Brava, not for the novice, Playa Cocles, and Playa Manzanillo at end of road...

www.crsurf.com

Costa Rica Pt Viejo is a euro backpacker scene and fun party town, stay in beaches south of town and rent bicycles. The raft the Rio Pacuare as a oneway day trip to San Jose, Top 10 river to raft in Americas, through indigenous indiands lands, gorgeous rainforest, jungle and waterfalls.

From San Jose, depends on interest, but I would get a bus straight to Jaco and surf there, not for beginners either, okay town, all the good surf towns and surf/beach scenes you don't have any time for IMO, maybe Tamarindo instead of Jaco, but thats 6 hours bus from SJ, though just 4 hours to Nica border, Tamarindo is a surf mecca for all levels and good nightlife to boot.

Once across Nica border, via busses from Liberia every 30 minutes to border, it depends on what you want, I would head to Ometepe for 3 nights, 2 nights in Granada as a base and then head out of MGA.

You really could spend the 3 weeks rushed in just 2 countries, so with long days of transport, you might want to consider internal flights, like from Panama City to Bocas, and from San Jose to Tamarindo.

The surf town in Nica is San Juan del Sur, but the good beaches and surf breaks you need to commute to, nothing in the town even to swim....Costa Rica has loads of great surf towns but you really don't have any time.

https://nicoyapeninsula.com

Save Granada (or better yet, Laguna Apoyo) for the end, as it is close to airport. Granada is touristy, and a few hours will suffice as far as the town itself is concerned.

Since you're already at the airport on arrival, and seeing as how Corn Islands are the most remote part of your trip, it would behoove you in terms of geographic economy to go there initially. Don't take no chance on the boat passage however - you don't want to end up like the 23 Costa Ricans that capsized when, despite forbidden, crossed in a gale in 2016. We stayed at Grace's. It was OK. I hung out at Tranquilo bar, but then I was pursuing Swedish chicks.

Ometepe: I enjoyed Hotel Landing in Ometepe, and Hotel Istiam over yonder around Santa Cruz. The latter was so cool, some people we shared a shuttle with split the drag place they'd reserved and moved in with us.

San Juan del Sur: not my favorite, but I don't think it criminal to spend 2 nights there. I really dug Hotel Estrella a funky old 1920s wood frame job right on the harbor.

I am unaware of any flights between Jamaica and Costa Rica. Keep in mind as well, there is the Onward Travel Requirements to enter Costa Rica on a oneway flight, you may need proof of a flight out of the country, at check in, for the flight to CR...(same for Panama)

Don't mix the caribe nations with Central America for travel, they don't have flights between them, other than Havana Cuba to some Capitals.

There maybe a flight between Jamaica and Panama City Panama...but it won't be cheap, compared to going via Miami, which is usually far more flights and cheaper.

As for the bus to Los Chiles to cross into San Carlos Nicaragua, there are buses departing San Jose every 2 hours in day;light I recall.

Keep in mind there is not a boat anymore from San Carlos to Ometepe or anywhere, its a long bus ride to Managua or fly. But the Rio San Juan area is well worth exploring regardless, getting a boat to El Castillo and the refuges there.