We first went to the Alps by direct Eurostar in 2008, when we had one daughter who was one year old.  The resort we favour is La Rosiere (although have also been to Les Arcs via train too).  Although not a massive skiing area, it's perfect for families in our opinion, although English-speaking ski schools perhaps not as strong as other resorts.

Last year (and by now we have 3 daughters, 10, 7 & 3), we decided to go via Paris, mainly due to the fact it was considerably cheaper, and almost the same travel time between St Pancras and Bourg St Maurice.
The only negative we found was cramming onto the Paris Metro with snowboard bags and luggage and 3 children!

This year just myself and my eldest daughter went to La Rosiere, again via Paris.
At £131 on the outward leg and £154 on the return (inclusive of an additional Paypal charge), for both of us, it was hugely cheaper than the direct Eurostar.

The journey started after school on Friday with a Metrolink trip from Bury to Manchester Piccadilly, then Pendolino to Euston.  We booked a room at the Premier Inn on Euston Road diagonally opposite to St Pancras, ready for the 08:30 departure of the Eurostar to Paris.
I printed the tickets from the self-serve machines in the terminal the night before, prior to stuffing ourselves in Pizza Express just below the Premier Inn.

I'd discovered an SNCF App, which let you scan the QR code off the tickets, which then logged your journey on the App - more of this later.

We got to St Pancras at around 07:30, stocked up on food for the journey and checked in.  It’s such a quick check in and short wait before boarding. We departed bang on time, and were soon racing under the Thames.

I went to the buffet to purchase four metro tickets (two for the outward and two for the return), but they only had carnets left (books of 10).  However some kind soul in the queue said they had four spare tickets and gave them us for free!  Result!

We arrived in Paris on time, which gave us 58 minutes to get to the Gare De Lyon.
It was much easier with fewer children this time, and found taking a shoulder Snowboard bag, just containing my snowboard much easier than a massive roller bag this we took last year containing two boards, two pairs of boots etc.

The SNCF App had sent a notification to my phone telling me our TGV was departing from Hall 1, which on arrival off the Metro we struggled to find initially, but I had an idea where it was.  Within 10 minutes of finding Hall 1, the SNCF App popped up another notification on my phone telling me what platform our TGV was leaving from.  I was really impressed with this, not needing to keep checking departure boards.

I'd booked seats with a table on the top deck, and the journey was really great.  Time to play a few games, read, listen to music and chill out.
Once on the single lines after Chambery, I love it when you first get to see the snowy mountains in the distance.

We arrived on time in Bourg, and in daylight, nice seeing the scenery on the outward leg, which is in the dark in January on the Eurostar Ski Train.
If you are staying in La Rosiere, and want to get the scheduled bus service (45 minute journey time), it leaves at 19:15, the Eurostar should get there at 19:03 - it can be late though!  (I think Altibus have added this 19:15, as earlier last year there was only a 19:00 departure)

We had a couple of friends who we are staying with who were travelling on the Eurostar, so we waited for them and then jumped in a pre-booked taxi.

The conditions were perfect, after they'd had around 8 metres of snowfall in La Rosiere, the first four days were big blues, and relatively warm, with freeze-thaw conditions, Thursday a white out and Friday sunny, cold and fresh powder.

We stayed in Les Cimes Blancs in Les Eucherts, great self-catering apartments, nice swimming pool and spa.  It's also worth checking out the local Ice Hockey game on a Wednesday night - really entertaining.

The return journey on the Saturday was trouble free on the French side, taxi back to the station, then TGV, Paris Metro, Eurostar and Euston to get a Pendolino back to Manchester.

The Eurostar Ski Train, which our friends were taking, was delayed by 1.5 hours due to the incoming night train being late in-bound.

So our TGV left before them, however they'd eventually overtake us whilst we were in Paris, as there was a more generous 1h 45 min transfer.

We really enjoy taking the train to the Alps, it is a much more pleasurable experience than the plane, you arrive feeling more relaxed, and there isn't a 2+hours coach transfer at the other end.

A few tips I've decided that works for us:

• Set up booking alerts with Loco2, so you are notified when tickets become available to get the cheapest fares
• If taking your own skis or snowboards, consider using lighter shoulder bags- much easier to stow on the trains and wrestle through the Paris Metro ticket barriers.
• If going via Paris, download the SNCF App and scan your tickets in, to get real time updates
• Buy your Paris Metro tickets from the buffet on the Eurostar on the way to Paris
• If there are a few of you, pre-book a taxi.  For us it was 75 euro up the mountain and 80 down.  The bus is 13 Euros each adult return I think, but consider where your accommodation is compared to where the bus stops!  Sometimes it is worth paying the extra.

Apologies if I've gone on too long, but I do like talking about high-speed rail -  especially when there is snow at the end of the journey!