There’s a golden rule about cruising: The school calendar decides how much you’ll pay for your trip.

When the kids are out of school, expect prices to be much higher than when classes are in session. And looking at the current schedule, it looks like this year passengers should expect to shell out a pretty penny for a summer cruise.

We’ve taken a look at the upcoming schedules for both Carnival and Royal Caribbean. Unlike past years, both cruise lines will have ships sailing from Galveston this summer. This wasn’t always the case.

If you can hurry up and book a cruise before the summer season or wait until after, then you can still find some pretty good deals. But if you want to sail during June, July, or August, then open up that wallet.

For example, the Carnival Triumph runs a regular 5-day cruise from Galveston to Progreso and Cozumel, Mexico. Book this trip right now for a December 1, 2014 trip and it costs only $279 per person for an interior cabin.

But that exact same trip on June 30, 2014 costs $629 per person for an interior cabin — $350 more! Remember also that those rates are per person. With two people sharing a cabin, the price difference adds up to $700. Of course, the price difference is even greater if you upgrade your cabin to an oceanview or balcony room.

The good news? While prices are higher in the summer, there is a good amount of competition. Royal Caribbean and Carnival both sail from Galveston, but don’t forget about Princess and Norwegian sailing from the Bayport Terminal in Houston.

Currently Princess and Norwegian don’t sail summer routes — choosing instead to move their ships for the summer. But as time goes on, we wouldn’t be surprised to see these cruise lines sail from Houston during future summers.

That would put four different cruise lines all sailing during the more expensive summer months, which would hopefully provide enough competition to lower summer fares. Click here to read our buying guide on finding cheap Galveston cruises.

Spring Break is almost here. Already the weather in Texas is turning much warmer — putting us the mood for some fun, sun, and water.

Of course, the perfect cure for that is a cruise. And thanks to the booming cruise industry in Galveston, you currently have more options for Spring Break cruises than ever before.

We count a total of 10 cruises leaving the island during the last three weeks of March. Meanwhile, the destinations — including Jamaica, Honduras and Belize — sound like the perfect cure to a long, cold winter.

Keep in mind that Spring Break is a pretty busy time for both cruises and Galveston. You can expect to pay more for your cruise during this time and just about any other time of year. Meanwhile, your hotel options may be a little more limited if you’re planning to stay on the island.

To give you an idea of what’s available, we’ve taken a peek at the cruise schedules to bring you all the options during Spring Break…

March 9-16 | Carnival Magic
7-Day Eastern Caribbean (Key West, Freeport, Nassau)
Starting at $799 per person

March 9-16 | Navigator of the Seas
7-Day Western Caribbean (Roatan, Belize City, Cozumel)
Starting at $914 per person

March 10-15 | Carnival Triumph
5-Day Western Caribbean (Progreso & Cozumel, Mexico)
Starting at $719 per person

March 15-20 | Carnival Triumph
5-Day Western Caribbean (Progreso & Cozumel, Mexico)
Starting at $489 per person

March 16-23 | Carnival Magic
7-Day Western Caribbean (Roatan, Belize City, Cozumel)
Starting at $619 per person

March 16-23 | Navigator of the Seas
7-Day Western Caribbean (Jamaica, Grand Cayman, Cozumel)
Starting at $654 per person

March 20-24 | Carnival Triumph
4-Day Western Caribbean (Cozumel, Mexico)
Starting at $349 per person

March 23-30 | Carnival Magic
7-Day Western Caribbean (Montego Bay, Grand Cayman, Cozumel)
Starting at $559 per person

March 23-30 | Navigator of the Seas
7-Day Western Caribbean (Roatan, Belize City, Cozumel)
Starting at $744 per person

March 24-29 | Carnival Triumph
5-Day Western Caribbean (Progreso & Cozumel, Mexico)
Starting at $429 per person

If you’re a Royal Caribbean fan, then you have 10 million reasons to be happy right now. It has just been announced that the cruise line and the Port of Galveston have reached an agreement that will bring dozens more sailing dates, a larger Royal Caribbean ship, and $10 million in port improvements to Galveston.

According to BizJournals.com, “the port will invest about $10 million to expand its Cruise Terminal No. 2. Plans include adding about 60,000 square feet to the terminal, bringing it to 150,000 square feet with a seating capacity of about 1,000.”

Cruise Terminal 2 is where Royal Caribbean ports.

In exchange for the improvements, the cruise line has agreed to add 30 sailings in 2014 and 2015, with a ship porting in Galveston year-round. Before 2014, Royal Caribbean’s service had been seasonal.

In addition, the company will bring a larger ship to Galveston when the terminal improvements are completed next year.

The current ship sailing from Galveston — Navigator of the Seas — is a Voyager-class ship measuring 1,021 feet long and carrying 3,100 passengers.

The next step up is a Freedom-class ship. This class of ship measures roughly 1,100 feet long and can carry up to 4,500 passengers. That’s almost a 50% increase in passenger count. In other words, this will be a major move up for Galveston cruisers.

To us, this news is proof of Galveston’s soaring popularity in the cruise world. And we only expect more in the future. With millions of people within a few hours of the port, there’s no reason that it can’t continue to grow as one of the busiest cruise ports in America.

In the next few weeks, Galveston will welcome a new cruise ship to its port — Royal Caribbean’s Navigator of the Seas.

The ship arrives for the winter sailing season on November 24, replacing the Mariner of the Seas as Royal Caribbean’s Galveston-based cruise ship.

So what can you expect from the new liner?

Frankly, if you sailed on the Mariner, then the Navigator will seem very familiar. Both ships are part of the cruise line’s Voyager class of ships.

The Navigator of the Seas measures 1,020 feet, just like it’s sister ship. Meanwhile, she has capacity for 3,100 passengers and more than 1,200 crewmembers. In total, the Navigator has a staggering 15 decks.

Built in 2002, the ship has all the modern cruise features and entertainment. That includes a casino, ice-skating rink, rock wall, basketball court, a three-story dining room, nearly a dozen different places to eat, a full-sized theater, multiple pools and much more.

The Navigator of the Seas is coming to Galveston after spending the summer cruising the Mediterranean from Civitavecchia, Italy.

Once in Galveston, the ship will sail the traditional 7-day cruises to the western Caribbean with ports of call like Roatan, Jamaica, Cozumel, Grand Cayman and Belize.

One exciting thing is that Royal Caribbean has decided to keep the Navigator of the Seas in Galveston year-round instead of leaving in April as its ships have done in years past. That means many more cruising options during the summer.

Note that the Navigator will leave Galveston for a few weeks in January. During that time it will go to drydock for upgrades including a FlowRider surf simulator, an outdoor movie theater and a revamp of its dining options.

Photo: Josh Friedman Luxury Travel

It’s a day five years in the making… now it’s just around the corner.

Built in 2008, the Bayport Cruise Terminal in Houston has sat dormant since it has been built. Outside of a few cruises following Hurricane Ike, the terminal hasn’t seen any traffic.

That’s about the change. On November 5th, Bayport welcomes its first dedicated cruise ship — Princess Cruise Lines’ Caribbean Princess.

Here are a few details of what to expect. The Caribbean Princess is 952 feet long, was built in 2004 (refitted in 2011), and can hold more than 3,000 passengers.

She will be taking Houston cruisers on 7-day trips to the Caribbean, sailing a regular schedule every week to Cozumel, Roatan, and Belize City.

Princess will have the port to itself for several months. Bayport’s other tenant — Norwegian Cruise Lines — doesn’t arrive until October 2014.

In the meantime, cruisers in the Houston area now have an option that’s about 45 minutes closer than Galveston and more competition between cruise lines could result in lower fares.

For more information about getting to the Bayport Terminal and parking, visit this page. For a calendar of cruises from the port, click here.

Photo: Eric the Fish