One of the things I wanted to do was make either a Viking Helmet or Dragon wings for each of the children invited. When I sent out the invitations I asked if the parents could let me know which one their child would like to be. We only had one child that changed his mind on the day and thankfully we had a spare Viking Helmet for him.
I used Lael Viking Helmet Pattern from Mamachee but if you can't crochet you can always get your sewing machine out and make this DIY Viking Helmet. Another quick option would be to make these cardboard and duct tape Viking Helmets.
More How to Train Your Dragon Party Ideas:
Astrid Costume - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-astrid-costume.html
Dragon Wings - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-dragon-wings.html
Pin the Fire on the Dragon - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-pin-fire-on.html
Felt Toy Dragons - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-felt-toy.html
Dragon Eggs - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-dragon-eggs.html
How to Train Your Dragon Cake - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-cake.html
Viking Helmets - http://littlesliceofhome.blogspot.co.nz/2015/04/how-to-train-your-dragon-viking-helmets.html