I need advice for the best way to get from Heathrow 3 to Paddington on the tube. I will have 21 students in tow and am looking for the best places to change in order to avoid stairs with luggage.
Here is some advice I got for a trip from Heathrow to Bayswater 2 years ago. Is this still the best?
Take the Piccadilly line from Heathrow to Hammersmith. Get off and on the other side of the same platform will be the District Line (direction Upminister) then stay on that train until Earls Court. Get off and on the other side of the same platform will be the District Line (direction Edgware Road) where I can get off at Bayswater. (This time we will stay on and get off at Paddington.)

Or the Journey Planner says Piccadilly Line towards Cockfosters to Hammersmith. Get off and with no walking or stairs/lifts/escalators take District Line towards High Street Kensington. Get off and with no walking or stairs/lifts/escalators take the Circle or District Line towards Edgeware Road to Paddington.

Any advice on what is best would be very much appreciated especially since we arrive at Heathrow at 6:50 AM on January 1st.

By far the best way to get to Paddington is by train using Heathrow Express or the cheaper Heathrow Connect.

No changes are involved.

Thanks Robert. I did know about both of those options, but we can't afford that unless you know of a way to get a student price or group discount.
Judie

Judie, the two sorts of tube advice you've quoted are the same (you can't get a High St Kensington at Hammersmith, you have to change at Earl's Court). Be aware though, at that time on New Year's Day there may only be a train every half hour from the airport - not sure what that would do for overcrowding, but at that time of day there won't be many locals using the service. And I'm not sure what sort of further waiting there might be at Hammersmith and Earl's Court.

Heathrow Express is not operating until the afternoon of New Year's Day. Heathrow Connect has still not published its New Year timetable:
http://www.heathrowconnect.com/default.aspx?pageid=2.

It may be that they're working on the lines that day (which would explain why HEX wouldn't be operating). Its normal Sunday service appears to be half-hourly at best - I'd suggest emailing them to ask what the position is.

Heathrow Connect would be quicker than the tube, but it would be more expensive (at £6.90 per person): it's not clear whether you need to get on the tube for Bayswater station if you arrive at Paddington (which would be an extra cost and complication), or whether you could walk from Paddington. Bear in mind too that if you all get Travelcards for zones 1-2 at Heathrow, the add-on for your journeys to and from Heathrow on the tube would be only £1.

The only other alternative would be to try to hire a coach of some sort, but that must be hopelessly expensive on New Year's Day - especially that early.

I have nothing material to add to Patrick's excellent advice.

I would say that I would still be prepared for anything: Have the kids pack as compactly as possible, and not pack more than they COULD carry up a couple of flights of stairs. You never know when a station could be closed, or a line rerouted.

Furthermore, the platforms are not huge, particularly at Earls Court, and your fellow travelers will thank you if your group and their gear is well-organized.

The trains also don't always stop for long, so if somebody goes back for a backpack, they might get separated from the group. Make sure EVERYONE has the full plan on where they're going, and what to do/how to regroup if you get separated. Learning to use public transportation is an important life skill, if they don't have it already, they should learn (I'm assuming they're around high school age).

I have seen many, many school groups from the Continent taking the Tube all over London (sometimes very young ones in groups as large as yours with a single chaperon!) and everyone, chaperon included, seems to make it home alive.

Have an amazing trip!