We've done the googling for you and found crafts that children can make that will make great gifts that mothers will want to keep. There's plenty of Mother's Day crafts here that don't require too much preparation or require items that are hard to find.
Use your choice of clay, paper clay etc depending on resources and drying time available. Children can tap into their creativity for decorating these useful bowls.
A clever of using handprints with the craft supplies you have in your service already. Adaptable for children of different age groups.
Another way of combining a child's handprint into an image. Would make a good card for varying children's age groups.
No need to hunt down coloured paper doilies - buy the white ones from the supermarket and have the children paint or colour them.
Simple idea for babies and very young children. Older children can cut out the handprints themselves, attach them to the straws and decorate, write or draw on them.
Use recycled, secondhand or donated containers and plants. Use found items from the garden such as small stones and bark for decoration.
An idea that doesn't require too many supplies and will look great in Mum's garden. Children's names and the year could be written on the bottom on the rock.
Here's an activity that could also cover learning about bees. An environmentally friendly and clutter-free Mother's Day gift with a difference.
A simple and budget friendly gift for children to make with supplies you probably already have in your service. Other items could easily be substituted for buttons.
Clever use of recycled egg cartons - would be suitable for a range of ages to accompany a card for Mum.
These hearts would be great gifts at any time of year and could be made with varying amounts of input by children of different ages.