This resource is designed to teach students how to use stick and ink. There are three differentiated worksheets, which means you get three versions of each worksheet.
1) For the least able - this has a faint image that they can work over.
2) For the majority - this has faint marks in a few places to help them with the overall shape.
3) For the most able - This just has the image of the shell to copy.
There is also a WAGOLL (What a good one looks like) which clearly shows that stick and ink can be used to make a range of marks and tone. (They must let that ink run out!) Also a mark making sheet.
I would teach this in two lessons. 1st lesson mark making for 3/4 of the lesson and then start drawing a few guide lines lightly in pencil on their shell. 2nd lesson, stick and ink shell.