People can also donate gifts to go towards a Christmas shoebox, or make a monetary donation.
She said the hardest age to buy for was 13 to 16 and the easiest was 4 to 6, and that was reflected in the boxes donated so far.
"Whatever ages we don't have enough of we can go and buy some stuff to put in boxes."
McElwain helped run the initiative last year when it launched in Northland and has taken over the main organising this year.
She said the boxes were "for people who can't afford Christmas".
Last year more than 1000 boxes were given to children across Northland. McElwain said she thought last year the initiative was more of a hit because it was new.
"But it's still doing really well."
The Christmas in a Shoebox initiative is also being run separately in Kaitaia and Dargaville.
McElwain said her family in Christchurch and Auckland have donated to the Northland cause and she has been blown away by what some people have donated.
Boxes are due in by December 20.
McElwain has been organising with community organisations such as Women's Refuge, Barnardos, Youth Space, Ngati Hine and others to identify families who will receive the shoeboxes filled with Christmas goodies.
She has also been taking nominations from members of the public.
Just like last year, McElwain is enlisting firefighters to help deliver some of boxes in Whangārei.
The community organisations will collect theirs to distribute and she will deliver some herself as far north as Kaikohe, she said.
To get involved, look up Christmas in a Shoebox Whangarei/Northland on Facebook.