How to deal with a student lacking commitment

First of all, people are not mind readers; so first tell the student that he/she needs to work harder. and then:

Longer Time Intervals: This worked for me for number of students. Basically double the time intervals between meetings. So for example, if you meet the student every week, tell him/her that his/her progress is not satisfactory so meet me in two weeks time and tell me what you did.

Warning With a Help of a Senior: Then give a warning for the next time interval, and tell the student if he/she keep working like this, you will not support him/her anymore. For this, it is better to have a senior lecturer (e.g., head of a group) in the meeting as well.

Refuse of Support With a Help of a Senior: Then, if the student progress is not satisfactory, have another meeting with the student and with the help of a senior lecturer let the student know that you did you best and because of the student's lack of progress you are not willing to work with him/her anymore. So, he student needs to find another supervisor to work with him/her.

First, a student must meet you half way. Otherwise, there is nothing much you can do. In this case, you walk away. Not everyone can be 'saved' no matter how much you care.

(1) is the issue lack of respect? Maybe he/she sees you as a PhD student only or that there is some cultural issue. The former can be remedied by involving your supervisor. As for the latter, there is no solution apart from asking the student to change supervisor,

(2) are the tasks too vague or big? Maybe break it down a bit more; start with 1+1 and build up to ODE for example. Setting a task that is well above a student's ability will kill his/her motivation.

(3) is he/she suffering from any mental issues or has personal problems? How is his/her score in other subjects? Usually these issues will affect all subjects. If the student is poor academically, you need to adjust your expectation

(4) have you discussed with the student how to work in a project based subject? Maybe he or she is at lost how to 'study' and get high mark, especially with a student supervisor.

Edited: based on your comment above, sounds like you have an incompetent student. So I would set an easy task and get him/her out of the lab! On this I have had students who have observed their teachers in their home country perform an experiment but never done one themselves! So when they are asked to prepare something it is like flying a plane after just having read the manual; so it is not unreasonable your student will want to cover up any incompetencies.

I would strongly consider revoking the student's laboratory access (or recommending this action to the appropriate authority; in some labs everyone has this authority). This student appears to be unprepared for laboratory work and may be a danger to themselves or others. Of course, this depends on the degree of hazard associated with your laboratory. Mine has substantial dangers which require lab workers to commit to follow procedures. If you do not feel permanent sanctions are warranted, you could offer the student the opportunity to earn their access back by performing safety/ethics/classroom training elsewhere.