Best way to get from Paris CDG airport to this Paris accommodation?

[toolatetobed]

We are going on a short break to Paris. Have booked accommodation on Boulevard Richard Lenoir near Place de la Bastille. Have a metro map, but find my eyes glazing over a bit when I try to work out best way of getting from Paris CDG airport to our accommodation via public transport! Does anyone just know the answer?

Take the RER (light suburban rail) Line B from CDG to Gare du Nord. Transfer there to the Métro, Line 5, Direction Place d'Italie. Bastille will be the seventh stop.

Public transport in Paris is really simple once you get your head around it.

Thanks very much. What do I need to ask for when I buy tickets, do I name the destination Metro station? (Or are all tickets sold via machines anyway so that I won't need to speak to anyone?) I'm assuming I can get a through ticket that covers both the RER bit and the Metro bit? Also, my children are aged 13 and 10. Will they be entitled to a child ticket that is cheaper than the adult one? TIA